This is a bit weird problem that I am facing while trying to login in Windiows. There are around 3 pc at my office. When I try to login Windows on welcome screen it freezes. Nothing works there. Even after hitting ctrl + alt + del nothing happens. I am not able to figure out the problem here. Before this use to work. While the other two looks like working fine. Only the system that I am using hangs a lot on welcome screen.