Thought I would post to suggest s possible solution:
win7 64bit with AVG free and comodo for many many months working flawlessly. This morning found windows startup hanging with no programs responding and task bar semi-loaded with icons(only comodo/sound and network loading). After trial and error, I realised that after some minutes, startup would continue fine, with comodo defense+ poping up for a net framework .exe . Even though I checked “remember me” and tried it for a couple of times, system wouldnt return to normal, and it was clear that defense+ was the culprit. Disabling defense+ from inside comodo options solved the problem, didnt really need it anyway, but got me quite frustrated as to why it would just randomly stop working fine… a new update messed defense+ up , perhaps?