As some of you may have picked up last week the Windows 7 beta build, that was announced yesterday, made available today for MSDN and TechNet subscribers and will be made available in several hours to the first 2.5 million people clicking the download link, contains a bug that corrupts *.mp3 files, when opened.

Note:
Apparently the beta release of Windows Server 2008 R2, the server version that accompanies Windows 7 does not suffer this bug. The bug is also not confirmed to be part of build 6801 of Windows 7.

The problem

In Windows 7 Build 7000 ("The Beta") Windows Media Player 12 will shave approximately 2-3 seconds off the beginning of MP3 files when:

• You have set Windows Media Player settings to retrieve information from the internet and to update files. These are the default settings when you select the "express" option during setup;
• You edit metadata for MP3 files from within Windows Media Player or Windows Explorer.

But only when:

• The header of the MP3 file is larger than 16KB

The solution

Microsoft Knowledgebase article 961367 offers an update package for this specific problem in this specific test build of Windows 7. The update package will be available from January 9, alongside the Windows 7 Beta.

The update package was released on TechNet and MSDN alongside the Windows 7 Beta ISO files in both x64 (3.47 MB) and x86 (1.86 MB) versions.

Predictably Microsoft will release the update to Windows Update on the first Patch Tuesday of 2009 on January 13 to pick up any Windows 7 installations that were deployed and don’t have the update packaged applied yet.

Concluding

I guess the Beta disclaimer exists for a reason…
When you deploy Windows 7 Build 7000, also deploy the KB931367 update package.

Further reading

KB961367 Fixes DVR-MS Playback in Media Center 7
Windows 7 Beta and patch
Windows 7 Beta kan mp3-bestanden beschadigen Dutch
WARNING: Windows 7 Beta Eats MP3s, Fix Coming
Warning: Windows 7 beta could corrupt your MP3s

Disclaimer Beta Software

The information on this webpage applies to software from Microsoft that was in testing phase but utilizable by experienced users by the time the webpage was written. This software has not been released for sale, distribution or usage for the general public. The information on this webpage and the beta software are provided "as is" without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose.