Avast broken: Can i still bootscan?

[Gunfingers]

My computer has been sharing thumbdrives and now i think it's caught something. Unfortunately whatever it is it prevents Avast! from running. It seems to be tied to shutting down certain services. Obviously i can't use Avast! to find it, so i would like to do a bootscan and see if that fixes the problem. Is there a way to schedule a bootscan without actually running the program?

[wyrmrider]

try a scan from safe mode  press F8 at boot  Start> programs etc
do you have any anti-spyware installed you could scan with?

[Lisandro]

Is there a way to schedule a bootscan without actually running the program?

Run:
C:\Program Files\ALWIL Software\Avast4\sched.exe /A:"*" /archives