Windows 7 - WMP Being weird

I rendered a recording file into H.264 MP4, but for some reason WMP won't play it. I tried installing Shark007's Windows 7 codec (x32 & x64) and setting both applications to 'Shark007 SUGGESTED settings' but it didn't help.
I recommend you open this:

1st of all, please know, the 64bit app affects playback in Media Center
The 32bit app affects most other players such as the default WMP

If you are not a LiveTV user, I suggest that you disable the Microsoft Video decoder on the SWAP TAB. Test.

The suggested settings disable Media Foundation on the SWAP TAB
This is benificial for M2TS playback but can break MP4 playback.

If the 1st suggestion didnt work, or is not for you,
press [Reset All]
test.

None of that helped.

In fact, it made the situation even worse. Now the AVI file won't play...

In that case, you probably need to update the codecs themselves.
Uninstall current installations. upgrade scenario's often cause problems too.

MajorGeeks is your source for up-to-date releases.

How would I do that? The only codec I've installed apart from the ones that are integrated with Windows is the Lagarith Lossless Codec.

In the installed Settings Applications (there are 2, one for 32bit players and another for 64bit players)
Go to the Help TAB, press the button [UNINSTALL]

Get new releases here . . . Win7codecs - x64Components addon

Sorry, I was just about to come back here to update my last post. I think the legendary file (.avi file) was corrupt/damaged.
But this is something else that's weird that only happened when I uninstalled the Windows 7 codecs:



This is with every single video file btw.

the graphic in the righthand lower corner represents the program you have associated that filetype to open with. It has nothing to do with codecs.