System shuts itself down (restarts), Shut down innitiated by NT AUTHOR

Hi, I've been having problems with the NT AUTHORITY/SYSTEM (C:/WINDOWS/System32.exe) Shutdown message, error code 203. My computer appears to be clean, but I dont think it is. I contacted Microsoft and they said it was a device driver, but I cannot locate the faulty driver. I posted this topic in the "HijackThis Logs and Spyware/Malware Removal" thread, got help from Noviciate and was then told to post here. Here is the link to that thread: http://forums.tomcoyote.org/index.php?show…=71121&st=0
Any help would be greatly appreciated! Thank You.

Does this happen to be the Error Screen that appears?
[external image: Posted Image]

Just a side note here:
I am totally impressed with the extent to which Noviciate went beyond the call of duty to assist you.
Clearly a considerate and knowledgeable helping person. My respects to Noviciate!

In the meantime, we can explore a few other options here.

Hi Dough: Thanks for your help and I totally agree with your comments re Novitiate. He's been great help! Now, the message is similar to the one you posted. In addition, I now get a blue screen (5 code) constantly. I freed some disk space (I only have one [c:]. Total of 71.4 GB and only 6.60GB free. After that clean-up I was able to connect to the Internet and so far no blue screen. Finally, in one Spysweeper detected a Backdoor-Rustock Trojan. Seems to be enough of a headache! Any suggestions? I really appreciate your help.