I've tried adding it using the "Optional Features" function, I've tried installing it from the command line, I've tried downloading several difference versions of Media Feature Pack with no luck.

Judging by the Windows support forums, I'm not alone. Some people seem to get it to work, others keep getting the same cryptic errors I have seen while trying to install it. If I click on the WMA files outside of Band in a Box the media player that came with Windows 11 plays the WMA file no problem.

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