If you check your WinXP you have probably Downloaded and installed (perhaps automatically) the WinXP SP3 module.
The WinXP SP3 module and further updates from Microsoft have caused mayhem worldwide, and I have experienced major problems here, initially thought to be AVG free v8+.
However, because the SP3 and further "Updates" from Microsoft have mostly crashed Security Software, best to try and go back to your setup before the SP3 and further updates.
There has been discussion that Microsoft have allowed these problems to persuade MS Windows users to upgrade to MS Vista, but all the various Vista Operating Systems have many troubles yet to be "fixed' by Microsoft.
Advice with be to remain with XP, get updates as far as SP2, and no further.
Alternative is to instal and ditch Microsoft forever.
Kind Regards....
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