I recently acquired a Trojanhorse Dialer virus & can't get rid of it. I want to download McAfee Antivirus, but I can't do that until I uninstall AVG6. I've tried uninstalling, & even went to add or remove programs, but it says it can't uninstall because a shell.dll file is missing. What are my options???? I've tried everything I can think of & now I'm desperate.