[ddouglass]

Let's try this. Uninstall (again) Microstudio. Do the Regedit again and delete just the Microstudio folder. Go to C:\Program Files\Micro Technology Unlimited\ and delete only the Microstudio folder.

Restart the computer. Then re-install. If this doesn't fix it then something outside of Microsoft is preventing it from opening. Because this should re-install everything used by the program.

It may be that one of the other programs you installed did interfere with Microstudio. Even if you have uninstalled them the registry additions for those programs will still be there as well as other files they put in the Windows folder and in your user profile. Hopefully a complete removal and re-installation of Microstudio can restore what is needed.