xcellent tricks and techniques of Google Hacks

ws_ftp.ini is a configuration file for a popular FTP client that stores usernames, (weakly) encoded passwords, sites and directories that the user can store for later reference. These should not be on the web!

That's some good stuff. Just copy/paste the text into your own WS FTP ini file and you're good as gold (assuming you're using the same version). Don't forget - even if they have taken the file offline, use the "cache:FULL_URL/wsftp.ini" to see the contents.
probably one of the best exploits I have seen in a long time, when I did it there were about 20 vulnerable computers, just recently there was 4 so I hope whitehats got to this before anyone else. really nice !!

To see results; just write in the (http://www.google.com/) search engine the code:

intitle:index.of ws_ftp.ini

==============================================

Frontpage.. very nice clean search results listing !! I magine with me that you can steal or know the password of any web site designed by "Frontpage". But the file containing the password might be encrypted; to decrypt the file download the program " john the ripper".

To see results; just write in the (http://www.google.com/) search engine the code:

"# -FrontPage-" inurl:service.pwd

==============================================

This searches the password for "Website Access Analyzer", a Japanese software that creates webstatistics.

To see results; just write in the (http://www.google.com/) search engine the code:

"AutoCreate=TRUE password=*"

==============================================

This is a query to get inline passwords from search engines (not just Google), you must type in the query followed with the the domain name without the .com or .net.

To see results; just write in the (http://www.google.com/) search engine the code:

"http://*:*@www" bangbus or "http://*:*@www"bangbus

Or

http://bob:bob@www

Or

http://admin:*@www

==============================================






This search is a cleanup of a previous entry by J0hnny. It uses "parent directory" to avoid results other than directory listings.

WS_FTP.ini is a configuration file for a popular win32 FTP client that stores usernames and weakly encoded passwords.

To see results; just write in the (http://www.google.com/) search engine the code:

filetype:ini ws_ftp pwd

Or

"index of/" "ws_ftp.ini" "parent directory"

==============================================

Microsoft Frontpage extensions appear on virtually every type of scanner. In the late 90's people thought they where hardcore by defacing sites with Frontpage. Today, there are still vulnerable servers found with Google.

An attacker can simply take advantage from administrators who 'forget' to set up the policies for Frontpage extensions. An attacker can also search for 'filetype:pwd users'.

To see results; just write in the (http://www.google.com/) search engine the code:

filetype:pwd service

==============================================


Not all of these pages are administrator's access databases containing usernames, passwords and other sensitive information, but many are! And much adminstrated passwords and user passwords, a lot of emails and the such too…

To see results; just write in the (http://www.google.com/) search engine the code:

allinurl: admin mdb

==============================================

DCForum's password file. This file gives a list of (crackable) passwords, usernames and email addresses for DCForum and for DCShop (a shopping cart program(!!!). Some lists are bigger than others, all are fun.

To see results; just write in the (http://www.google.com/) search engine the code:

allinurl:auth_user_file.txt

==============================================

This search brings up sites with "config.php" files. To skip the technical discussion, this configuration file contains both a username and a password for an SQL database. Most sites with forums run a PHP message base. This file gives you the keys to that forum, including FULL ADMIN access to the database. To see view the PHP files; there in lies the catch. Browsers are made to process the commands of PHP before display, so if no commands, nothing to show. You can't use that persay to get into the config file, but it would show potential threats if someone got into server anyway. (If that happens you're basically boned anyway, not much around that.

To see results; just write in the (http://www.google.com/) search engine the code:

intitle:index.of config.php

By the way, to know how to view the PHP file contents, you can use this code:

intitle:"Index of" phpinfo.php

==============================================

These files contain ColdFusion source code. In some cases, the pages are examples that are found in discussion forums. However, in many cases these pages contain live sourcecode with usernames, database names or passwords in plaintext.

To see results; just write in the (http://www.google.com/) search engine the code:

filetype:cfm "cfapplication name" password

==============================================

FlashFXP offers the easiest and fastest way to transfer any file using FTP, providing an exceptionally stable and robust program that you can always count on to get your job done quickly and efficiently. There are many, many features available in FlashFXP.

The flashFXP.ini file is its configuration file and may contain usernames/passwords and everything else that is needed to use FTP.

To see results; just write in the (http://www.google.com/) search engine the code:

filetype:ini inurl:flashFXP.ini

==============================================

The encryption method used in WS_FTP is _extremely_ weak. These files can be found with the "index of" keyword or by searching directly for the PWD= value inside the configuration file.

There is an easy way to decrypt the hash, use the decryptor at:


http://www.codebluehacks.com/Tools.php?ID=1

Or

http://www.hispasec.com/directorio/laboratorio/Software/ws_ftp.html

To see results; just write in the (http://www.google.com/) search engine the code:

filetype:ini ws_ftp pwd

==============================================

These files contain cleartext usernames and passwords, as well as the sites associated with those credentials. Attackers can use this information to log on to that site as that user.
To see results; just write in the (http://www.google.com/) search engine the code:

filetype:log inurl:"password.log"
==============================================

Web Wiz Forums is a free ASP Bulletin Board software package. It uses a Microsoft Access database for storage. The installation instructions clearly indicate to change the default path and filename (admin/database/wwForum.mdb).
vendor: http://www.webwizguide.info/web_wiz_forums/

The forum database contains the members passwords, either encrypted or in plain text, depending on the version.

Please note: this search is proof that results can stay in Google's index for a long time, even when they are not on the site any longer. Currently only 2 out of 9 are actually still downloadable by an attacker.

To see results; just write in the (http://www.google.com/) search engine the code:

filetype:mdb wwforum

iPod Access for Windows does for Windows users what it has been doing for Mac users for over a year. iPod Access for Windows is the premier application for transfering songs from your iPod to your Win XP/2000 computer. Most iPod transfer utilities must fetch ID3 tag information by opening every music file and fetching information. iPod Access is able to utilize the iPod internal database so that it can display your iPod's contents almost instantly. This includes tag information from protected AAC files that have been purchased from the iTunes Music Store and all playlist information. Version 2.0 also adds Playlist Cloning and the ability to add songs directly into iTunes.

With a simplified user interface including song filtering by Artist/Album or Composer/Album you can find the songs you need to copy and even listen to them directly in the main window. When copying songs iPod Access can organize songs into Artist/Album folders or Composer/Album folders and change the file names if desired.

iPod Access also provides one button full sequential music backups. By pressing “Backup” in the toolbar you can speed up the process of regular backups. iPod Access will by default only copy new songs added to your iPod so you don't have to remember what you have added.

What's new in this version:
# New Copy Engine up to 3x faster.
# Improved iTunes compatibility.
# Fixed 'currTrack is null' error.
# Fixed bug that would cause folders to be created but no songs.

Product Requirements:
* Windows 2000/XP/Vista
* Quicktime v6 or higher
* iPod Software v1.2 or higher
* iTunes v6 or higher
* Windoes Script Engine (wscript.exe)

This product is designed to run on the following operating systems:
* Windows XP
* Windows 2000
* Windows Vista

Code:
http://rapidshare.com/files/11795241/cr-iare.rar

A small collection of tricks.


Theory:

Well the theory of this technique, is simply phone redirection. The excellent thing is, with home phones, you can redirect to telstra error messages. All those 12722 numbers can be used to create some really weird mesages when people are ringing.

Technique:

1. Okay, now the phun part. Firstly, take your list(appended on to the bottom of this file, credits to Decimalz).

2. Select a number that you wish to redirect to. I myself, am fond of the 127224* range.

3. Enter *21#

4. Ring your home number, and hear the message you selected.

5. To turn off enter #21#

List of Forwarding functions:

*21# - Immediate forward to target *61# - Forward on no answer

*61*# Forward to target on no answer, after time delay.

*24# - Forward on busy tone.

With the above technique, and below list(any number can be used, not just this list). This technique is really easy to do, and also introduces some basic principles of call redirection. It is also so very amusing, especially when you know someone will call and you dont want to talk. Its amazing how often telstra disconnects my line when i know they will ring.

Appendix. A.

The following numbers were taken from: Decimalz - Guide to Phreaking for a New Generation, part 1

Telstra Test Numbers

All test numbers for Telstra begin with 12722. so phreakers get to your nearest payphone and start scanning. here is the list so far.

12722 0 CND send status

12722 123 Own number RVA (old number 19 123)

12722 199 Ringback (old number 199)

12722 40001 "The number you have called is not available from this service"

12722 40003 "This service is not connected"

12722 40004 "Your attempt to use this feature has been unsuccessful"

12722 40005 "The feature you have tried to to use is not provided"

12722 40006 "The number you have called is not connected"

12722 40007 Recorded busy tone

12722 40008 "Congratulations. You have accessed a standard network test message recording"

12722 40009 "The person you are dialling now has a new telephone number. To find out the new number please call Telstra's changed number information service"

12722 40010 "The number you are calling is currently unavailable"

12722 40020 "The number you have called is not compatible with your equipment"

12722 40023 "The service type you have requested is not provided"

12722 40024 "You have attempted to call via a service provider network.
All lines are currently busy. Please delay your call for a short time"

12722 40033 "This number is not in service. Please use the alternate number for the person you are trying to contact"

12722 40034 "This telephone number cannot be dialled with an area code. Please try again without using the area code"

12722 40035 "Thank you for using Telstra for your long distance calls"

12722 40036 Congestion tone

12722 40037 Congestion tone

12722 40064 "Operator assisted calls are not permitted to this number"

12722 42209 "Your Telstra call waiting feature is on"

12722 42210 "Your Telstra call waiting feature is off"

12722 42211 tone... "Your Telstra call waiting feature is on"

12722 42212 tone... "Your Telstra call waiting feature is off"

ah the old call back..

12722 199

*note that number will only ring..so not like the old 199 number where you would hang up and then the phone would ring.

Optus Test Numbers

Test numbers for Optus all begin with 12723, so phreakers once again start scanning. 12723 12 Own Number RVA (old number 127 2311)

12723 22 1kHz

12723 99 Ringback



BILLING TO THE PAY-PHONE NEXT TO YOU
---------------------------------------------
As stupid as it may sound, billing to the pay-phone next to you is
sometimes a very easy way to pull off free phone calls from pay-phones.
First of all, you'll have to check if the phone next to you can receive
incoming calls. If it doesn't say anything about "NO INCOMING CALLS" on
the front, it probably does. Next, check that the pay-phone next to you has
a phone number. If it doesn't, pick up that phone and dial 1-800-666-6258.
After listening to about 30 seconds of BS, you'll hear the area code and
number of that pay phone. Next, dial up our old friends ITI, at
1-800-288-2880. After the dial tone comes on, wait for the operator. As
mentioned in Way #3, you have to give the number you're calling "from" and to,
but make sure they are in DIFFERENT STATES. Then when ITI wants to know how
you want to bill the call, say "Third-Party", and give them the number of the
pay-phone that's right next to you. ITI will call to "verify" the charges,
at which time you answer, change your voice, and of course accept the charges.
Please note that ITI is not as stupid as they were earlier this year (although
they are still VERY stupid), and they do have a good deal of pay-phones
"locked out" from billing. But of course, a very large number of pay-phones
still exist that AREN'T locked out of ITI, so have a ball while you still can.




To get free calls (local only) on a payphone, you need these items:

1. A Payphone
2. A sharp object
3. A metal wire

To get a free call on a payphone, you need to follow this procedure:
1. Enlarge hole in the speaking portion of the phone.
2. Poke the wire into the hole of the speaking part.
3. Cross the other end of the wire with the phone cord.
4. While hearing a loud noise, dial the number
5. Lift the wire up right after dialing.

Warning: Do not attempt a long distance call!!!!!!!!!!!!!!!
You will feel a slight shock if attempted!



Money Mad


Section 1:The coin slot

For every 5 cents you put in a phone, a sound is made. After you put
the coins in the slot, they pass through a totalizer which counts them.
They then collect in a hopper. To empty out the hopper, all you have to
do is activate the coin relay. Payphones sometimes hold $100 or more.
To activate the relay place 5 cents in the phone. Stick a magnet up the
coin slot about 5 inches. Now remove the front panel of the phone. You
will see a series of wires. Cut the red and green wires. Now in the
front of the panel you will see three screws. Touch the green wire to
the third screw. Better have a hat ready, because alot of change is
gonna come flooding out. Isn't this fun?

Section 2:free credits
If you have a friend in germany you need to call this sections for you.
One of the cheap things about pay phones is they depend on tones to tell
them you inserted money. Well if you have a red box these tones are
easily duplicated, but i want to show you how do it without boxes in
this file. Now Some thing you need are...
A set of screwdrivers. You will need both philips and flathead. Now
open the front panel of the phone and cut the red and green wires. Take
the cover off the top of the phone and insert 5 cents. You should hear
nothing. Find a green wire coming from the coin slot down to the
hopper. Disconnect that wire. Now take off the case and you will see a
small switch. Move the switch. This sets the totalizer backwards 1.
Now put the hopper cover back on and reconnect the wire. Go back to the
front panel. Feel to the right of the two screws. You should feel 4
jumpers. 1 of the jumpers should be disconnected. Reconnect it. Now
cut the top jumper. You should hear a loud pop. Now touch the green
wire to the second screw. You will hear the sound of twenty five cents
being inserted. You now have 30 cents credit. Repeat as many times as
you need. Now reconnect the green wire and dial your number.
GTE Notes:
The green wire will be white. The red one will be blue. The totalizer
is located at the bottem of the front panel.

I hope this insight wii provide a good use for those who want to do business on the web..

Surf to Google and perform a search on "Internet Merchant Account". The results are staggering (472,000 results!) If you have created a web based business and need to accept credit card payments, your choices are limitless. Before you partner with a provider, take time to understand the different components of internet credit card processing, and know what to look for in a merchant provider.


How It Works

Accepting credit card payments through your web site actually requires multiple components. Between a paying customer and your bank account, three layers exist:

Payment Gateway - This is the code that will transmit a customer's order to and from an internet merchant account provider. The payment gateway provides you the ability to accept customer billing information (credit card number, credit card type, expiration date, and payment amount) and the necessary validation steps that must be followed before the credit card is actually billed.

Internet Merchant Account - A Merchant Account is an account with a financial institution or bank, which enables you to accept credit card payments from your clients. The payment gateway actually transmits the billing information to the internet merchant account provider. Unfortunately, most local banks do not provide internet merchant account capability.

The main reason why most local financial institutions or banks do not want to provide online merchant accounts is because transactions conducted over the Internet are totally different from face to face transactions where a signature is required to authorize the purchase. This makes online transactions prone to credit card fraud. Fraud protection should be one of your primary considerations when choosing an internet merchant account provider.

Web Site - Regardless of which merchant provider and gateway service you choose, your web site will need to integrate with your service providers. Most providers include detailed web integration instructions.


How Much Does It Cost ?

Understanding the total costs of your merchant provider can be tricky. Remember my Google example - there are more merchant account providers than there are people looking for internet merchant accounts so ask questions and be picky! Typically, an internet merchant account will have three types of costs:

- Up Front Application Fees
- On Going Fixed Fee
- Discount Rate
- Fixed Transaction Fee
- Termination Fees
- Miscellaneous Fees

Let us discuss each type of cost:

* Up Front Application Fees

Many internet merchant accounts will require an up front application fee. This fee, supposedly, is to cover their costs for processing your application. In case you choose not to open an internet merchant account, they still cover their initial costs. Although common, many providers waive these fees and I recommend that you choose a provider that does not require an up front fee.

* On Going Fixed Fee

Most all internet merchant providers require a monthly fixed fee or "statement fee" as it is commonly named, which is simply another way to cover their costs and make money. You will be hard pressed to find a provider that does not require this type of fee on a monthly basis. However, do not choose an internet merchant account that requires more than $10 per month. Additionally, most internet merchant providers require a monthly minimum (usually $25). The bottom line is that you will be paying at least $25 per month (on top of the monthly statement fee) for your account.

* Discount Rate

Usually, the discount rate will be between 2 and 4 percent. The discount rate is the sales commission the provider earns on each sale. For example, if the discount rate offered is 3%, and you receive a sale over your web site for $20, you will owe 60 cents to your internet merchant provider.

* Fixed Transaction Fee

Usually between $0.20 and $0.30, the fixed transaction fee is the fixed fee portion of each sale. Unlike the discount rate, the fixed transaction fee is the same for every transaction. Whether you get a $1 sale or a $100 sale, the transaction fee will be the same.

* Termination Fee

A bit more hidden in the small print, a termination fee can apply if you cancel your merchant account within a specified period of time (usually within one year). But beware, some merchant providers require a three year commitment!

* Miscellaneous Fees

If a customer requests a refund and they want their credit card credited, an internet merchant provider will charge you a separate fee (usually between $10 - $20). Read the contract carefully, as other special fees may apply.


Putting It All Together

Now that the different fees have been explained, let us look at an example set of transactions to help understand what an internet merchant account may cost your business on a monthly basis.

I have created a simple formula to help you calculate your monthly charges:

Total Charges = Statement Fee + Number of Transactions x (Average Sale x Discount Rate + Fixed Transaction Fee) + (Number of Chargebacks x Chargeback Fee)

For example, let us see you sell widgets over the internet. The sales price for each widget is $10. You typically have 100 sales per month and about 5 people request refunds (chargebacks). For this example, let us assume you have signed up with Jones&Jones internet merchant account services and have the following terms:

Discount Rate - %2.5
Statement Fee - $10
Fixed Transaction Fee - $0.30
Chargeback Fee - $15

Using my formula above, your monthly Jones&Jones charges will be:

Total Charges = 10 + 100 x (10 x .025 + 0.3) + (5 x 15) = $140

You can calculate your monthly sales revenue by multiplying your sales volume by your price:

Monthly Sales Revenue = 100 x $10 = $1000

Your internet merchant provider is costing you 14% of your total sales.


Making Your Decision

Before you choose and internet merchant provider, understand all of the cost components. Use your current or projected sales data to forecast what your internet merchant account costs will be. Planning ahead can save you time and money.

Choosing A Good Domain Name


Choosing a domain name for your site is one of the most important steps towards creating the perfect internet presence. If you run an on-line business, picking a name that will be marketable and achieve success in search engine placement is paramount. Many factors must be considered when choosing a good domain name. This article summarizes all the different things to consider before making that final registration step!


Short and Sweet

Domain names can be really long or really short (1 - 67 characters). In general, it is far better to choose a domain name that is short in length. The shorter your domain name, the easier it will be for people remember. Remembering a domain name is very important from a marketability perspective. As visitors reach your site and enjoy using it, they will likely tell people about it. And those people may tell others, etc. As with any business, word of mouth is the most powerful marketing tool to drive traffic to your site (and it's free too!). If your site is long and difficult to pronounce, people will not remember the name of the site and unless they bookmark the link, they may never return.


Consider Alternatives

Unless a visitor reaches your site through a bookmark or a link from another site, they have typed in your domain name. Most people on the internet are terrible typists and misspell words constantly. If your domain name is easy to misspell, you should think about alternate domain names to purchase. For example, if your site will be called "MikesTools.com", you should also consider buying "MikeTools.com" and "MikeTool.com". You should also secure the different top level domain names besides the one you will use for marketing purposes ("MikesTools.net", "MikesTools.org", etc.) You should also check to see if there are existing sites based on the misspelled version of the domain name you are considering. "MikesTools.com" may be available, but "MikesTool.com" may be home to a graphic pornography site. You would hate for a visitor to walk away thinking you were hosting something they did not expect.

Also consider domain names that may not include the name of your company, but rather what your company provides. For example, if the name of your company is Mike's Tools, you may want to consider domain names that target what you sell. For example: "buyhammers.com" or "hammer-and-nail.com". Even though these example alternative domain names do not include the name of your company, it provides an avenue for visitors from your target markets. Remember that you can own multiple domain names, all of which can point to a single domain. For example, you could register "buyhammers.com", "hammer-and-nail.com", and "mikestools.com" and have "buyhammers.com" and "hammer-and-nail.com" point to "mikestools.com".


Hyphens: Your Friend and Enemy

Domain name availability has become more and more scant over the years. Many single word domain names have been scooped up which it makes it more and more difficult to find a domain name that you like and is available. When selecting a domain name, you have the option of including hyphens as part of the name. Hyphens help because it allows you to clearly separate multiple words in a domain name, making it less likely that a person will accidentally misspell the name. For example, people are more likely to misspell "domainnamecenter.com" than they are "domain-name-center.com". Having words crunched together makes it hard on the eyes, increasing the likelihood of a misspelling. On the other hand, hyphens make your domain name longer. The longer the domain name, the easier it is for people to forget it altogether. Also, if someone recommends a site to someone else, they may forget to mention that each word in the domain name is separated by a hyphen. If do you choose to leverage hyphens, limit the number of words between the hyphens to three. Another advantage to using hyphens is that search engines are able to pick up each unique word in the domain name as key words, thus helping to make your site more visible in search engine results.


Dot What?

There are many top level domain names available today including .com, .net, .org, and .biz. In most cases, the more unusual the top level domain, the more available domain names are available. However, the .com top level domain is far and away the most commonly used domain on the internet, driven by the fact that it was the first domain extension put to use commercially and has received incredible media attention. If you cannot lay your hands on a .com domain name, look for a .net domain name, which is the second most commercially popular domain name extension.


Long Arm of the Law

Be very careful not to register domain names that include trademarked names. Although internet domain name law disputes are tricky and have few cases in existence, the risk of a legal battle is not a risk worth taking. Even if you believe your domain name is untouchable by a business that has trademarked a name, do not take the chance: the cost of litigation is extremely high and unless you have deep pockets you will not likely have the resources to defend yourself in a court of law. Even stay away from domain names in which part of the name is trademarked: the risks are the same.


Search Engines and Directories

All search engines and directories are different. Each has a unique process for being part of the results or directory listing and each has a different way of sorting and listing domain names. Search engines and directories are the most important on-line marketing channel, so consider how your domain name choice affects site placement before you register the domain. Most directories simply list links to home pages in alphabetical order. If possible, choose a domain name with a letter of the alphabet near the beginning ("a" or "b"). For example, "aardvark-pest-control.com" will come way above "joes-pest-control.com". However, check the directories before you choose a domain name. You may find that the directories you would like be in are already cluttered with domain names beginning with the letter "a". Search engines scan websites and sort results based on key words. Key words are words that a person visiting a search engine actually search on. Having key words as part of your domain name can help you get better results.

Fatal error: the system has become unstable or is busy," it says. "Enter to return to Windows or press Control-Alt-Delete to restart your computer. If you do this you will lose any unsaved information in all open applications."

You have just been struck by the Blue Screen of Death. Anyone who uses Mcft Windows will be familiar with this. What can you do? More importantly, how can you prevent it happening?

1 Hardware conflict

The number one reason why Windows crashes is hardware conflict. Each hardware device communicates to other devices through an interrupt request channel (IRQ). These are supposed to be unique for each device.

For example, a printer usually connects internally on IRQ 7. The keyboard usually uses IRQ 1 and the floppy disk drive IRQ 6. Each device will try to hog a single IRQ for itself.

If there are a lot of devices, or if they are not installed properly, two of them may end up sharing the same IRQ number. When the user tries to use both devices at the same time, a crash can happen. The way to check if your computer has a hardware conflict is through the following route:

* Start-Settings-Control Panel-System-Device Manager.

Often if a device has a problem a yellow '!' appears next to its description in the Device Manager. Highlight Computer (in the Device Manager) and press Properties to see the IRQ numbers used by your computer. If the IRQ number appears twice, two devices may be using it.

Sometimes a device might share an IRQ with something described as 'IRQ holder for PCI steering'. This can be ignored. The best way to fix this problem is to remove the problem device and reinstall it.

Sometimes you may have to find more recent drivers on the internet to make the device function properly. A good resource is www.driverguide.com. If the device is a soundcard, or a modem, it can often be fixed by moving it to a different slot on the motherboard (be careful about opening your computer, as you may void the warranty).

When working inside a computer you should switch it off, unplug the mains lead and touch an unpainted metal surface to discharge any static electricity.

To be fair to Mcft, the problem with IRQ numbers is not of its making. It is a legacy problem going back to the first PC designs using the IBM 8086 chip. Initially there were only eight IRQs. Today there are 16 IRQs in a PC. It is easy to run out of them. There are plans to increase the number of IRQs in future designs.

2 Bad Ram

Ram (random-access memory) problems might bring on the blue screen of death with a message saying Fatal Exception Error. A fatal error indicates a serious hardware problem. Sometimes it may mean a part is damaged and will need replacing.

But a fatal error caused by Ram might be caused by a mismatch of chips. For example, mixing 70-nanosecond (70ns) Ram with 60ns Ram will usually force the computer to run all the Ram at the slower speed. This will often crash the machine if the Ram is overworked.

One way around this problem is to enter the BIOS settings and increase the wait state of the Ram. This can make it more stable. Another way to troubleshoot a suspected Ram problem is to rearrange the Ram chips on the motherboard, or take some of them out. Then try to repeat the circumstances that caused the crash. When handling Ram try not to touch the gold connections, as they can be easily damaged.

Parity error messages also refer to Ram. Modern Ram chips are either parity (ECC) or non parity (non-ECC). It is best not to mix the two types, as this can be a cause of trouble.

EMM386 error messages refer to memory problems but may not be connected to bad Ram. This may be due to free memory problems often linked to old Dos-based programmes.

3 BIOS settings

Every motherboard is supplied with a range of chipset settings that are decided in the factory. A common way to access these settings is to press the F2 or delete button during the first few seconds of a boot-up.

Once inside the BIOS, great care should be taken. It is a good idea to write down on a piece of paper all the settings that appear on the screen. That way, if you change something and the computer becomes more unstable, you will know what settings to revert to.

A common BIOS error concerns the CAS latency. This refers to the Ram. Older EDO (extended data out) Ram has a CAS latency of 3. Newer SDRam has a CAS latency of 2. Setting the wrong figure can cause the Ram to lock up and freeze the computer's display.

Mcft Windows is better at allocating IRQ numbers than any BIOS. If possible set the IRQ numbers to Auto in the BIOS. This will allow Windows to allocate the IRQ numbers (make sure the BIOS setting for Plug and Play OS is switched to 'yes' to allow Windows to do this.).

4 Hard disk drives

After a few weeks, the information on a hard disk drive starts to become piecemeal or fragmented. It is a good idea to defragment the hard disk every week or so, to prevent the disk from causing a screen freeze. Go to

* Start-Programs-Accessories-System Tools-Disk Defragmenter

This will start the procedure. You will be unable to write data to the hard drive (to save it) while the disk is defragmenting, so it is a good idea to schedule the procedure for a period of inactivity using the Task Scheduler.

The Task Scheduler should be one of the small icons on the bottom right of the Windows opening page (the desktop).

Some lockups and screen freezes caused by hard disk problems can be solved by reducing the read-ahead optimisation. This can be adjusted by going to

* Start-Settings-Control Panel-System Icon-Performance-File System-Hard Disk.

Hard disks will slow down and crash if they are too full. Do some housekeeping on your hard drive every few months and free some space on it. Open the Windows folder on the C drive and find the Temporary Internet Files folder. Deleting the contents (not the folder) can free a lot of space.

Empty the Recycle Bin every week to free more space. Hard disk drives should be scanned every week for errors or bad sectors. Go to

* Start-Programs-Accessories-System Tools-ScanDisk

Otherwise assign the Task Scheduler to perform this operation at night when the computer is not in use.

5 Fatal OE exceptions and VXD errors

Fatal OE exception errors and VXD errors are often caused by video card problems.

These can often be resolved easily by reducing the resolution of the video display. Go to

* Start-Settings-Control Panel-Display-Settings

Here you should slide the screen area bar to the left. Take a look at the colour settings on the left of that window. For most desktops, high colour 16-bit depth is adequate.

If the screen freezes or you experience system lockups it might be due to the video card. Make sure it does not have a hardware conflict. Go to

* Start-Settings-Control Panel-System-Device Manager

Here, select the + beside Display Adapter. A line of text describing your video card should appear. Select it (make it blue) and press properties. Then select Resources and select each line in the window. Look for a message that says No Conflicts.

If you have video card hardware conflict, you will see it here. Be careful at this point and make a note of everything you do in case you make things worse.

The way to resolve a hardware conflict is to uncheck the Use Automatic Settings box and hit the Change Settings button. You are searching for a setting that will display a No Conflicts message.

Another useful way to resolve video problems is to go to

* Start-Settings-Control Panel-System-Performance-Graphics

Here you should move the Hardware Acceleration slider to the left. As ever, the most common cause of problems relating to graphics cards is old or faulty drivers (a driver is a small piece of software used by a computer to communicate with a device).

Look up your video card's manufacturer on the internet and search for the most recent drivers for it.

6 Viruses

Often the first sign of a virus infection is instability. Some viruses erase the boot sector of a hard drive, making it impossible to start. This is why it is a good idea to create a Windows start-up disk. Go to

* Start-Settings-Control Panel-Add/Remove Programs

Here, look for the Start Up Disk tab. Virus protection requires constant vigilance.

A virus scanner requires a list of virus signatures in order to be able to identify viruses. These signatures are stored in a DAT file. DAT files should be updated weekly from the website of your antivirus software manufacturer.

An excellent antivirus programme is McAfee VirusScan by Network Associates ( www.nai.com). Another is Norton AntiVirus 2000, made by Symantec ( www.symantec.com).

7 Printers

The action of sending a document to print creates a bigger file, often called a postscript file.

Printers have only a small amount of memory, called a buffer. This can be easily overloaded. Printing a document also uses a considerable amount of CPU power. This will also slow down the computer's performance.

If the printer is trying to print unusual characters, these might not be recognised, and can crash the computer. Sometimes printers will not recover from a crash because of confusion in the buffer. A good way to clear the buffer is to unplug the printer for ten seconds. Booting up from a powerless state, also called a cold boot, will restore the printer's default settings and you may be able to carry on.

8 Software

A common cause of computer crash is faulty or badly-installed software. Often the problem can be cured by uninstalling the software and then reinstalling it. Use Norton Uninstall or Uninstall Shield to remove an application from your system properly. This will also remove references to the programme in the System Registry and leaves the way clear for a completely fresh copy.

The System Registry can be corrupted by old references to obsolete software that you thought was uninstalled. Use Reg Cleaner by Jouni Vuorio to clean up the System Registry and remove obsolete entries. It works on Windows 95, Windows 98, Windows 98 SE (Second Edition), Windows Millennium Edition (ME), NT4 and Windows 2000.

Read the instructions and use it carefully so you don't do permanent damage to the Registry. If the Registry is damaged you will have to reinstall your operating system. Reg Cleaner can be obtained from www.jv16.org

Often a Windows problem can be resolved by entering Safe Mode. This can be done during start-up. When you see the message "Starting Windows" press F4. This should take you into Safe Mode.

Safe Mode loads a minimum of drivers. It allows you to find and fix problems that prevent Windows from loading properly.

Sometimes installing Windows is difficult because of unsuitable BIOS settings. If you keep getting SUWIN error messages (Windows setup) during the Windows installation, then try entering the BIOS and disabling the CPU internal cache. Try to disable the Level 2 (L2) cache if that doesn't work.

Remember to restore all the BIOS settings back to their former settings following installation.

9 Overheating

Central processing units (CPUs) are usually equipped with fans to keep them cool. If the fan fails or if the CPU gets old it may start to overheat and generate a particular kind of error called a kernel error. This is a common problem in chips that have been overclocked to operate at higher speeds than they are supposed to.

One remedy is to get a bigger better fan and install it on top of the CPU. Specialist cooling fans/heatsinks are available from www.computernerd.com or www.coolit.com

CPU problems can often be fixed by disabling the CPU internal cache in the BIOS. This will make the machine run more slowly, but it should also be more stable.

10 Power supply problems

With all the new construction going on around the country the steady supply of electricity has become disrupted. A power surge or spike can crash a computer as easily as a power cut.

If this has become a nuisance for you then consider buying a uninterrupted power supply (UPS). This will give you a clean power supply when there is electricity, and it will give you a few minutes to perform a controlled shutdown in case of a power cut.

It is a good investment if your data are critical, because a power cut will cause any unsaved data to be lost.