I'm afraid I can't be much help with your problem, but I think you should edit your last post to remove your email address (if it's not already too late) because your address could be 'harvested' to bombard you with spam.
As for the problem, you are getting the warning from Windows Defender (which is not a particularly well regarded program) plus an error message from Defender itself. One thing you could try is running an online scan to see if you get confirmation of an infection.
If you go to the Malware Removal forum, there should be a 'Sticky' thread at the top giving details of programs you could use. You could also try this;
http://www.eset.eu/online-scanner (read the instructions carefully if you decide to try it).