error 0x000000c1

Hello, i cant start avast, i get this error.(cannot start ashSimpl.exe).

That means ‘The file is corrupted’.
Do a repair of the installation.

Control Panel → Add/Remove Programs ->avast Antivirus → Repair.

I did an repair but it still wont work, i also downloaded a new install file, but still the same error, i cant start the on-acces scanner also, then i get the message error in rpc (Remote Procedure Call.