Chat causes reboot!!!

[zeretul]

When using chat rooms, any chat rooms, my system either
freezes or completely reboots itself at random times.

I have checked as instructed, and have the lastest
versions of my chat site software, the latest java
version, and my computer is NOT set to reboot on system
failure.

There are no error logs made on my event viewer, and no
other indication it ever happened.

As always, your help would be greatly appreciated.

P.S.
I have also noticed that since this became a problem, I
can no longer boot directly to the desktop, but instead
to the log-in screen which has had only one identity.

Thanks.

 

[Smile Extender]

Have you checked for viruses and spyware? You might have unwanted guests.

 

[zeretul]

Yes. I have McAfee Virusscan 7.0, firewall 7.0, and use
Ad-Aware 6.0 routinely.