How are you "running" it? I'd say you have some deep rooted problem in windows-- seeing as you've never actually run mIRC on the machine yet, it's not really an mIRC issue. mIRC needs only the "mirc.exe" to run, no other components.
The fact that you recently reformatted/reinstalled windows due to a "bad ass" virus leads me to think you didn't quite solve your "virus" problem, because this is some wonky behaviour that should never occur on a supposedly clean install.
