Up to this point I had downloaded a Star Trek WMV file from Amazon Unbox to one PC. Having experienced performance issues, I had copied it to another PC and learned that the WMV film was protected by Microsoft's Windows Media DRM (Digital Rights Managements). Finally I had dismantled the first PC and had built a more powerful PC to play the WMV file on. But when I installed the Unbox software and tried to import the film, I ran into errors. It seemed like Unbox was reluctant to grant a DRM license key.
At this point I was ready to consider this experience a small loss ($1.99) and move on, but curiosity got the better of me and I surfed to Unbox's site to see if I had a recourse. That's when I discovered that the downloaded film came with two license only. I guess that's the copyright regiment that Unbox was enforcing to prevent users from copying the file to unlimited devices and acquiring licenses for them. It would have been nice if Amazon had at least mentioned that point at the time of purchase. Armed with that knowledge I decided to uninstall Unbox from the other PC and in doing so Unbox must have revoked the license on that box leaving the film with one usable license. I was finally able to successfully obtain a license for the file and watch the movie on the new PC without encountering any issues.
Since the original PC was now discarded, I assume the first DRM license was lost forever. Perhaps if I had contacted Amazon and explained the situation, they might have reinstated that original license, but having finally been able to watch the episode in its entirety, getting the extra license was a moot point. I also don’t know if there is limit on the number of times a license can be surrendered and re-acquired.
Based on my experience I have decided that DRM is just not worth the hassle. There are too many restrictions, at least with the Unbox implementation. You pay a decent sum to purchase a movie (I saw some for about $15), you have to use the 1-Click button, Amazon gift certificates are not accepted, then you have to install a software you may not want, then you wait for the download, and you can only get two licenses for it, and you need decent computer power to decrypt and play the movie smoothly. You can't even burn it to a DVD to watch it on your TV. A colleague explained that if my TV had an S-Video interface, I could hook it up to the PC's S-Video port, start the movie on the PC and watch it on my TV. Fine, but why not just purchase a used DVD for less money and avoid all the hassle?
There might have still been other restrictions too. During the course of my research I ran into a number of posts that lamented the Unbox's licensing terms, such as the fact that Amazon can revoke a license for any reason without recourse. People were also wary of Unbox's software license agreement which essentially strips user's right to privacy and can freely wander around a PC and collect all sorts of information and relay data back to Amazon's servers. It reminded many of the Sony music CD DRM fiasco from a few years back. In that case the CD's installed a rootkit spyware on users' PC's which was nearly impossible to remove without damaging the operating system itself.
I haven't read the Unbox's agreement yet, so I can't comment on that with authority. I don't believe that Unbox's DRM implementation is as egregious as that of Sony's. The version I downloaded allows users to deactivate the service and the startup program and the downloaded movies play fine. The Unbox program however does need to run in order to purchase, download, and acquire a license.
All in all, I wasn't impressed with Amazon Unbox. I suppose the service does have its uses if you wanted to purchase a movie or a show on a whim, but there are alternatives that are cheaper and less onerous. By the way, the episode of Star Trek I downloaded was "The Enemy Within". It's one of the earlier episodes of the original series in which a transformer malfunction creates two Kirks with opposite personalities. One gentle and indecisive, and the other mean and aggressive. Ironically, Unbox might be Amazon's mean incarnation.