Hi BD, your suggestions were really good. I was facing a few problems with Heur myself for some days. It wasn't allowing both windows and McAfee to update. My programs were crashing and the high point was when my laptop told me that my Vista (32-bit Home Premium;came with my system) was not licensed and that Microsoft could not give me any more updates. I was initially concerned when McAfee kept telling me that it could not update its virus definitions. Finally,I uninstalled McAfee, ran AVG today. AVG detected Win32 Heur and the infected system file and its related reg file are now in the vault, set to auto delete in 2 days. Once i restarted my system, everything seems to be in order except for the fact that windows still cant seem to update either Defender or the usual Vista updates. Just for the record, I have my Windows Firewall up and when I did have McAfee, I had its firewall up as well. Now,with AVG's free version downloaded from the website, i just have the Windows Firewall. Unfortunately, I am not able to update AVG as well. I just dont feel like I have done everything but repeated system scans by AVG say that there are no more infected files. What more can I do??