The "Prefetcher" is designed to SPEED UP the boot process and the loading of programs in Windows XP. Certainly, it's not a bad idea to clean out the "Prefetch" folder on occasion because "old" links can be stored there, but overall, it's "good" to keep the files stored in the "Prefetch" folder.
Many users tweak the registry slightly so that the Prefetcher only stores the "boot" data and not the "boot and application" data. Click on the link below and read about the "Enablepretcher" setting in the registry. The "default" Value Data for most WinXP machines is "3". Some prefer "2". (Personally, I like the default, but each user might like to check and see which they prefer.)
For TroubleShooting Windows XP: Disable the Windows XP Prefetcher
http://www.windows-help.net/WindowsXP/troub-07.html
Hope this helps.
Grif
Boot up speed up
Xp on start first goes to Prefetch to establish all that you have previously used is available. So slowing down Boot-up
To clear temporarily, because Xp will put back as you use information into Prefetch
Go to C:\ Windows\Prefetch
There will be hundreds of entries
Press Control A i.e. Ctrl+A
This highlights all
Press delete key on key board Gone
Next time Windows will boot quicker until Prefetch is filled up again.

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