So you installed the Unbox player when you were logged in as one user at Amazon, and later you purchased and downloaded videos as another user?
Well you’re going to hell, says Amazon.
I’ve just spent half an hour poring exhaustively through every nook and cranny of the Unbox UI, Unbox executable files, and even trying to go through the Modify/Repair options afforded by Windows, all to no avail. So far as I can tell, the Amazon account that you chose when you installed Unbox is the one and only account that you will be using with Unbox, unless you uninstall the entire player and reinstall it.
This is one of the few times that Amazon has chapped my hide. Usually they are decent, reasonable people.
If any commenter knows of a trick to get around this, a gaggle of Google searchers will thank you for it. Me? I just uninstalled and reinstalled Unbox, and wrote a blog about it to pass the time while I waited for the install to download & finish.
Mega awesome commenter Nick Haas has the answer! Says Nick:
I think I figured it out on Windows 7 at least:
This folder contains another folder which you can just move somewhere else on your computer. The next time you open up Unbox, it will ask you to log in again. I logged in with my other account and also changed the Computer Name and the Download Folder to remind me which account this one was. I then downloaded a free movie with the new account and it worked like a charm. When you want to go back to your other account just switch back to the folder that you moved originally.