Windows XP shuts down byitself [when downloading torrents]

My HP cpu restarts byitself. I noticed it does this frequetly when I'm downloading torrents files. When my cpu reboots I receive this Error
windows cannot find
'http://oca.microsoft.com/resredir.aspx?sid=10&Bucket=0xdD1_ar5416%2b43aae$State=1&ID=166168d1-178c-4082-98c0-1abb87b5d553&LCID=1033&OS=5.1.2600.2.0
0010100.2.0'. Make sure you typed the name correctly, and then try again. To search for a file, click the start button, and then click Search.
does anyone know what to do. Thanks

 

This looks to me like you have or have had malware that played around with the Hosts or Winsock.

Altho normally this would not cause a lockup in itself.

Go here get and run Hijackthis and paste us a log file.
http://radiosplace.com/

Next

Start-run
type
cmd
hit enter or click ok

in the window that opens copy and paste each line below to the command prompt

netsh interface ip delete arpcache

ipconfig /flushdns

ipconfig /release *

ipconfig /renew *

ipconfig /registerdns

nbtstat -RR

netsh int ip reset reset.out

Reboot

then download and install the MVP hosts file
http://www.ericphelps.com/security/HostsInstall.vbs/
allow it access the internet
let it do it for all users
let it create a shortcut to hosts file

Do this reboot then check your problem.

Post another HJT log.

Bob