I'm running into a bug with BSS 5.1.1 installing(update?) while an older version is already installed. First, the "install" does not see, or notify regarding a previous installation. In this case the older version is 2.x and it's been installed in Program Files.
The new installer does not remove the old version even though the license has been invalidated for it. At the least older versions should be detected and the current installation should be stopped. And a message to the user to uninstall the previous version before proceeding would be helpful.
Since no one has bothered to post anything here on this ... the removal of a license does not remove the program for any app that I'm aware of, it just nullifies the use of the license and/or app itself until you put another one in. So yes, you would need to uninstall the old version ... but I'm guessing that since you were using "Such" an old version, it would have been common sense for you to uninstall it prior to installing the update or new version. That version is at least a couple years old which should have been a flag to you to start with.
Anyways, good practice to remove old versions if they are really old. Hopefully you got it all worked out in the end. :)
This happens because we switched to a different installer in version 5.0.0 which doesn't require admin privileges. Removing old installations would have been risky and we decided not to delete user files automatically. Instead we opted for showing a note on our download page to uninstall any old releases manually.
We don't plan on switching to different installers in the future, so this won't be a problem any more.