Explorer.exe taking 100% cpu time

[Guest]

Windows Vista Home Premium 32-bit.

Explorer (not iexplorer) is taking 100% of the cpu all the time. It is very
random when it happens and it seems to go away after 30-90 minutes from
starting. It may stop for an hour or so then consume the processor again. It
does not seem to have a pattern (no applications seems to trigger it). I have
used msconfig to kill my startups (windows services still run) and tried
using the system today like that but it still occurs. If I use task manager
to change the process priority to Below normal it still takes 100% of the cpu
but when another application uses the processor the explorer process goes
down until the application is finished so I get more response. The downside
of that being that every application i open is set to below normal and i have
to manually change it to normal. I have run hardware diags including memory
diags and found everything clean. Not sure how to proceed at this point. I
have run full scans for viruses and spyware. Any ideas?

Thanks,

 

[Guest]

This was happening to me before. I just upgraded my RAM to 2GB, and turned
off the paging file.

 

[Guest]

I was able to resolve the problem by reinstalling Vista as a Upgrade over top
the existing installation. It seems to have resolved the problem. I have been
using Vista all day and the problem has not re-surfaced. If the problem was
going to arise it would have done so by now. I think it's been resolved.