Can't acces any of my executables?

> Help, My McAffee virus protection detected a virus on a
> file labeled smssgj.exe which I told it to delete. Now I
> can't run any of my programs. I get the error "Windows
> cannot find 'C:\Program Files\etc. etc' (etc being the
> path and executable file name). Make sure tou typed the
> name correctly and then try again.' Anyone have any
> idea's or possible resolution paths? Thanks...