This started yesterday. Firefox hangs, using 50-60% CPU and no network
activity. I restored the C drive and MBR from a week ago (Aconis
image) and it got better for a little while but it was back. Then I
tried refreshing Firefox, same thing, OK for a while then it started
slowing down again. There is no particular page activity.
Event recorder shows this
Warning TCP/IP has reached the security limit...
Error ...DCOM got error the service cannot be started because it is
not enabled or no enabled devices attempting to start gupdate with
argument /comsvc

Another alarming info message is remote console app started. I thought
I had that turned off.

To make matters worse Internet Exploder is broke too so I don't really
have a way of comparing them. IE8 says it thinks I have a firewall
setting wrong but I turned Norton and Window firewall off still no
joy.

I am starting to think I have been hacked or that Firefox is the
virus.
My next step may be to unplug the other drives to be sure they are not
infected and putting the bug back on, Format C: and reload with an
even older image from a remote drive. See how long that runs OK