The .wms Extension Is Removed From Windows Media Player

When you click on links to .wms files after you apply the Windows Media Player update that is described in the following Microsoft Knowledge Base article, .wms files no longer automatically start Windows Media Player:

This behavior occurs because the update that is described in Q320920 removes the "application/x-mx-wms" MIME type that is associated with Windows Media Player for Windows Media skin files (.wms).

This behavior is by design.

There is no vulnerability or flaw in the behavior of Windows Media skins. The security mechanisms that govern their use continue to be safe. As part of an ongoing security review, Microsoft decided that the association of .wms files with Windows Media Player was not necessary for the basic operation of the feature. Because of this, and in accordance with the principle of least privilege, the association was removed.