I don't know but a couple things I'd try is a file search for files created at the same time of your initial install in case it stores configuration data there, or uninstall it then delete the folder it was installed in if it left any config files behind.
Another thing to try is a registry monitoring program to see which reg keys are read when the program is launched, then uninstall it, then delete those keys (make sure they are specific to only this app), then reinstall.
Another thing to try is restoring your OS partition backup to put system state back to where it was before the first installation. Everyone makes those backups before any changes, right?
It's yet another example of why, that things can come out of nowhere that you don't expect, especially if you let windows or apps update themselves automatically.