Solved: Help needed - Win32 trojan

When I booted this morning Avast found this trojan in c:\windows\system32\athcfg. At the same time I got an error message saying TWCU.exe couldn't start. I asked Avast to try to repair it, but apparently it couldn't as the same thing happened when I rebooted. I then had Avast put the faulty file into the chest. I have restored to last Tuesday, but, while Avast doesn't mention a problem, TWCU still fails to start. I am currently on my wife's lappie as with no TWCU I can't reach the internet on my machine.

Additional information. I have just done a wall to wall virus check and it seems the virus has replicated itself in the restore folder, which would explain why it is still there after two attempts to restore to two separated earlier dates.
The virus is Win32: Trojan-gen (other)
The version given is 080919-0, 19/9/2008
While Avast was doing the wall to wall I moved the one in C:\WINDOWS\system32\ to the recycle bin. The one in c:\System Volume Information\-restore\ I twice moved to the recycle bin and once, renamed with a .vir extension, to C:\program files\Alwin Software\Avast4\DATA\moved\ and it just keeps reproducing itself in the restore folder.
(All the files I moved are still where I put them.)
Someone, HELP!