If you are dealing with several different formats that won't play, you may want to look into downloading a codec pack. In the past I have used K-Lite codec packs. Anyone else have other codec packs they like?
Here is a safe place to get codecs from: http://download.cnet.com/windows/?tag=hdr;snav
The above suggestion will really only help if it is a missing codec problem. You may also want to provide more details about what "Windows Media Player won't play" means. Error codes? Program crashing?.....
I had Windows XP on my computer. Upgraded to Windows Vista and now the Windows Media Player won't play. How can I fix this? I have looked for other versions. Haven't found one yet.
Thanks,
vblanton2@verizon.net

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