I'm running Windows XP Home. For quite a while I've had Windows Media Player 10, and everything worked including Video Files.

Then I upgraded to WMP11, which was alright, but after getting a bunch of music from a friend in .M4A audio format, I decided to switch over

to Itunes. I did that, got annoyed at Itunes, switched to Winamp and RealPlayer, everything fine so far. Even converted all my music to MP3, because I thought it was a universal file format. Then along comes this bloody update from Microsoft, and I couldn't play ANY video files or DVD's (still can't) after the updates were installed, not even WMP11 wouldn't play them .

So now I want to switch back to WMP11, and what happens? It doesn't even want to play .wma, .wav, or any other file format that it should be able to play. Anyone got any ideas? Also, my computer refuses to play DVD's. So any ideas ?

So it "won't play", "doesn't even want to play", "wouldn't play", "still can't play" and "refuses to play"... but, what does actually happen ? Any error message ?

What happens if you right-click on a media file (.mp3) and chose "Open with Windows Media Player"?

Whenever I try to play pretty much any media file type (including Window's types) I get this error message "Windows Media Player encountered a problem while playing the file. For additional assistance, click Web Help." This has also happened when I try to open a file with right-click and open with Windows Media Player.

I also tried uninstalling WMP11, which rolled back to WMP10. I tried it with WMP10 and get this error message: "Windows Media Player encountered an unknown error. This can occur when another program or operating system component encounters a problem but does not communicate the nature of the problem to the Player."

Hope the info helps...

Its all about the Audio Video Codecs.

When you removed WMP11 it removed Windows Media Runtime that is necessary part to play .wma, .wav, .wmv files.

One more thing, WMP11 doesn't play .VOB (DVD file) due to DRM (Digital Rights Management) policy.

So You have to install Codec Pack and you can go for: Vista Codec Pack

It works with Windows XP or earlier version of Windows also.

Ok, thanks! I'll try the codecs then.

One thing though, the codecs are for WMP10, right? What if I were to upgrade back to WMP11? Also, all files weren't and aren't working on both versions.

Its works in both !! version of WMP

Thank you so much everyone for your help!!

I'll definetely try that codec pack as soon as I can!!