From my quick research it looks like there are a lot of causes of this error including conflicts between legitimate programs (usually virus scanners and IE or messenger progs) as well as illegitimate programs such as spyware and viruses.

My first thought was to ask whether you had installed anything new prior to playing RTW (when it crashed)?

If you didnt, then I'd guess the focus has to be spyware/virus.

It may also be helpful if you post the exact error message.