By sending an email message to every one of its subscribers, Microsoft today informed that it will add some drastic music restrictions to the MSN Music service. "I am writing to let you know that as of August 31, 2008, Microsoft will change the level of support to be offered for music purchased directly from MSN Music prior to November 14, 2006. As of August 31, 2008, we will no longer be able to support the retrieval of license keys for the songs you purchased from MSN Music or the authorization of additional computers. License keys already obtained as of August 31, 2008 will continue to allow you to listen to songs on all the computers that you previously authorized for service. We wanted to send out this notification well in advance to remind you to backup your music and to provide you sufficient time to confirm license keys for the songs you've purchased from MSN Music." the mail says. The music restrictions do not just apply to authorizing new computers. If you for example upgrade from one Microsoft OS to another, you'll need to reauthorize all tracks once you install the new Windows OS. Microsoft launched the MSN Music Store in September, 2004, in an effort to compete with Apple's iTunes but after two years on November 14, 2006 the company started redirecting MSN Music Store shoppers to the Zune Marketplace. Now Microsoft is taking the next step by deleting its MSN Music license servers.