Although Windows is very stable, blue screen of death error messages will crop up now and again.
With Windows XP the errors can’t be easily understood or analyzed.
when your computer begins to freeze you should uncover what is occurring, you know it’s time to start running a few tried and trusted tests.
Don’t spring to the conclusion that your complete system has been corrupted and start reformatting the hard disk and reinstateing the operating system. 
Though this may cure the computer problems, sometimes it won’t.
Reformatting your system should be something to start thinking about when all else has failed, if you are getting blue screen of death error messages.
Restarting your system is my 1st suggestion as to what to do in this situation. 
About half an hr would be ample time to leave it off.

The windows defrag should then be run.

If you don’t already have a registry cleaner, your built in defragmentation program does a fairly good job at clearing your hard disc.

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To run a defrag.

1. Go into start menu, “all programs”.
2. Take the accessories option.
3. You will now be able to click disc defrag which you will find in system tools.
4. Just click “analyze” in the disc defrag window.

After analyzing a window will tell you if you need to defragment the volume.
There’re lots of registry cleaners you can download which come with free scans, that do a much better job than a Windows defragmentation.

You might be sat waiting hours on end for your defrag to run it’s course.

Try to ensure you haven’t got any work to be doing on your computer when you schedule a defrag.
possibly when you are turning in for bed.
You’ll discover XP burying files in hard to access corners and losing them fairly often. It is much more difficult for your computer to get access to them when required fast. We need our most commonly used files in easy access areas and this is precisely what a registry cleaner will do. . They are also well known for gathering all of the scattered defragmented files up and scraping them from your hard drive. These include all the files that cause your system to crash.

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There’re more ways than one to set off blue screen of death error messages. It’s a possibility that your PC’s ram is not operating correctly. You can simply insert another one into your mother board if faulty ram is indeed your problem.

Would there be too many networks running on your PC at the same time?.

Many connections to Internet, office servers or Blue-tooth networks, is likely to pack up your virtual space in your memory. Try disconnecting your computer from the various networks and then reboot it. If the problem was lots of networks connected then your system will run far quicker when restarted. The same problems will come back when all of the networks are reconnected. 
Don’t run your printer or blue-tooth networks unless they are needed.

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