I've been reading a few threads in this great board, and it seems other people had the same problem as me. Everytime I turn on my PC, I get the error message saying that svchost.exe cannot be found. In addition, the trojan modified my registry keys which prohibit me from using the Task Manager and some other of the basic Windows tools. I run Ad-aware, and it tells me that I have the Ciadoor trojan, which is then easily removed, except for the fact that it comes back every time I reboot the system. I attached the HJT file, hopefully this will make things clear. Thanks in advance!