mIRC doesn't have a hideapp.exe, if your copy does then you definately are not running a version downloaded from mIRC.com. What I would suggest you do is uninstall mIRC, run a virus scan, then reinstall mIRC but ONLY DOWNLOAD mIRC FROM THIS SITE. If you download it from somewhere else it is possible that someone has modified mIRC and included some infected files (which is why you should run a virus scan).
