It appears that Microsoft’s decision to close MSN Music has rankled more than just customers: a new statement and letter (PDF) from the Electronic Frontier Foundation accuses Microsoft of betraying its music customers by abandoning its store’s DRM servers.

“This decision means that every customer that bought an mp3 from you—with the good faith expectation that despite the irritating DRM she would be able to continue to play the song on a variety of devices—faces losing music if she upgrades her PCs or her hard drive crashes after August 31, 2008,” wrote EFF Executive Director Shari Steel, in an open letter to Microsoft dated April 29.

Previously, Microsoft’s Rob Bennet suggested that customers who wanted to keep their music beyond the blackout’s August 31 date had to either preserve their computer’s functionality or export their purchased music to a CD and then re-rip the music back to mp3 files. This solution, as previously discussed, forces Microsoft customers to “invest more time, labor and money in order to continue to enjoy the music for which they have already paid.”

The EFF’s statement announcing the letter further elaborates: “The odd thing about this suggestion is that the more music you bought from Microsoft -- the more of a loyal customer you were -- the more time you are expected to spend sitting in front of your computer, burning discs and then re-importing them (degrading the sound quality in the process).”

In a previous interview with CNET, Bennett said that “no one ever foresaw being in this situation,” and expressed that the best long-term solution for people “who want to buy music from Microsoft” is to switch to Microsoft’s Zune platform.

Steele’s letter to Microsoft closes with a series of instructions that Microsoft “should immediately and publicly” follow if it wants to rectify the situation:

• Issue a “full public apology” to MSN Music customers.
• Offer its customers refunds, or, copies of their music in a DRM-free format.
• Ensure that MSN Music customers have adequate access to purchase receipts.

Additionally, Steele wants the company to work with its industry partners to remove DRM in the future, and to make sure that MSN Music customers are made aware of the above steps by, at minimum, “advertising in major music magazines and newspapers in every major U.S. city, as well as targeted keyword advertising.”