My Question is how do i know if my computer is completely clean of any infections? I will give you a little background info. Before I knew about the existence of this forum and others like it i was running Avast anti-virus free edition with windows firewall and Firefox with no add-ons only, I recently reformated and reinstalled WinXP OS Home SP3 due to Win32agent Rootkit infection being picked up on an Avast Boot-time scan. Since then I have researched and installed Comodo, Malwarebytes, Spybot S&D, Spywareblaster and Firefox with no-script add-on. I was in the process of downloading SuperAntispyware from the actual website to round out my security software but when i went to install it there was a pop-up that said "The System Administrator Has Set Policies to Prevent This Installation" while i was currently logged on as a adminstrator. Also on the internet connections i was unable to disable the network connection and got this pop-up "It is not possible to disable the connection at this time, This connection may be using one or more protocols that do no support Plug-and-Play, or it may have been initiated by another user or the system account." Nothing got picked up by Comodo Defense+ which is set to paranoid. I immediately ran Avast Boot-time scan, MBAM scan, and SpyBot scan but nothing was found. I ended up using system restore to an earlier point before I downloaded SuperAntispyware. After using system restore I was able to download and install SuperAntiSpyware and after researching the network connection problem I used Cathook commands and fixed it. I have run multiple scans with all four programs and nothing has been found since. I still do not know how the above mention problems occurred. I did not change anything myself other that installing the security software mentioned. How do I know the computer is clean other than a full re-install which I would like to avoid if possible? Is this some remains of the win32agent? Do I need to run Hijack this? Any ideas?