WMP wont play mp4 anymore ?

[Ronin-7]

I have a strange problem that no doubt I was the cause of but cannot rectify it and was wondering if anyone could help me out.

I have the CoreAVC Directshow codec installed along with an DS AAC decoder and Haali Media splitter and I was able to play MPEG 4 AVC trailers I downloaded in WMP and MPC perfectly fine [of which they still play fine in MPC].

Anyway I normally use MPC for everything but just recently I wanted to test something so I opened WMP and tried to open an King Kong 720p trailer MP4 file and it came back saying WMP does not support the file type even though it had played it before (this goes for any other MPEG 4 file I tried as well).

I tried reinstalling all the above programs I mentioned to no effect but if I rename the .mp4 to .mkv it plays fine in WMP so this is bugging me as to why, anyone know what to do ?

[bond]

when playing the file, does icon of the haali splitter show up in the taskbar?

try to render the file in graphedit and check what filter is used

[Ronin-7]

Graphedit gives it the all clear the CoreAVC and CoreAAC decoders are properly linked up to the correct outputs (Haalis media splitter icon also appears in the systray).

When I try to open a .mp4 file in WMP it doesn't even get to the stage of opening it I get an error box saying this file type is not supported with close or more information, the more info button just shows the error code for which WMP says when it comes across an unsupported file type.

I suspect some part of my registry is corrupted in how WMP treats MP4 files as if I rename the file either .m4v or .mkv it plays perfectly fine in WMP, problem is I haven't the faintest idea were to look in the registry and reinstalling WMP did nothing.

[On other thing in that if I try to play .m4v or .mkv in WMP it gives the warning box saying it may or may not be able to play do you want to try and the tick box for do not show this message in the future whereas with .mp4 it gives the error message instantaneously]

[bond]

yeah, propably some wmp-error on your system. try reinstalling it, or even better uninstall it and use a better player ;)

[Ronin-7]

Yeah I dont even use WMP, MPC is what I generally stick with but I'm one of those people who just can let something go and it will be annoying me in the back of my mind knowing that it isnt working :(

I'll try uninstalling WMP via the add/remove system components and see what happens & go on a hunt through the registry jungle for anything that might lead to a clue as to whats going wrong.

Update: Success!
After uninstalling WMP10 and reverting to WMP9 it worked in WMP9 so it must be a setting somewhere specific to WMP10, after reinstalling WMP10 of course it still didn’t work so I trawled the registry and found a few places of note to surgically delete.

Unfortunately I could not locate the specific entry in the registry which was the cause of this so I ended up deleting about 6 "media player" groups if you go through the registry and look under each section for a software/microsoft/media or media player you will find the areas where the preferences or saved info that WMP retains is kept after removing about 6 of these from the registry and starting WMP 10 again it played the files without any problems whatsoever, thank god for that as it was gnawing away at me : )