Error Loading Explorer.exe ReInstall Windows

Microsoft Windows 98

hi,

I'm new please be nice!

NOTE THIS HAPPENS EVERYDAY!

While playing Pool on Yahoo Games on several occasions
the SOUND WENT OUT & a WHITE DIALOG BOX has popped up
with the ERROR MESSAGE as follows exactly "Error Loading
Explorer.exe You Must Reinstall Windows" then only choice
is "OK" after Hitting ok the Start Button and Taskbar
disappear she can then continue to play but once she
leaves that window the
computer crashes.

I've not been able to get her to try to replicate the
problem in any other program or window if this is enough
information for someone to assist us please reply.

thanx for your assistance
WM
When did she last check for viruses?
3 days ago Virus Updated and Run and it happened 3 days
since!

thanx
WM

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