How do you...

You install it and read the documentation. It's that easy.

Jam it back in, in the dark.

First make sure the video is really H264 encoded. What is the container type?
What kind of demuxing capabilities you have (Haali Media Splitter, etc.)?

Is H264 support enabled in 'ffdshow video decoder configuration'?
Which version of ffdshow are you using? What kind of CPU are you using?
Which version of MPC are you using?

You see, you don't provide enough information to help you. You only say: It doesn't work.
And I ask you: What is not working? Are there any error messages? BSODs, etc.?

How ya doing, buddy?

The VideoLAN client is not your first choice if you want to watch H264 encoded media. It's because release of stable versions of VLC doesn't happen often. Why is that a problem?

You see that VLC heavily relies on the ffmpeg package, which does all the video decoding (apart from the WMO part) and ffmpeg is a project that is rapidly developing. Now the latest VLC release is quite old and so is the ffmpeg library included in VLC. AFAIK the ffmpeg version used in VLC is much older then the one used by ffdshow.

Now the main point: H264 decoding is currently in massive development in the ffmpeg tree. To get best decoding performance its best to use the latest SVN copy (that compiles). So you really want to use the newest ffmpeg version possible. And because most of you don't know how to compile software it's best to use latest builds of ffdshow. VLC's ffmpeg is just to old.

How ya doing, buddy?

Originally Posted by Jamma

Yes, it really is H264 encoded.

You didn't tell me the container type.

Originally Posted by Jamma

WMP is the only player I want because I don't like having shitloads of player/codec packs cluttering my computer.

WMP is full of spycode, you know?

Originally Posted by Jamma

Yes I'm eggagerating a little, but I've just had my computer initilized for the fifth time. I want the basics, nothing else.

You won't kill your system just by installing VLC. I also doubt it writes anything significant to the registry. It's simply unpacking and go.

Originally Posted by Jamma

"Is H264 support enabled in 'ffdshow video decoder configuration'?"
Apart from the read-me, I can't actually open anything in the ffdshow folder.

What about opening 'ffdshow video decoder configuration' through using the start menu (I think the windows guys still use it).

Originally Posted by Jamma

ffdshow-20020617

You can read, can you? The version is from 17.06.2002! Thats 4 years! A bit outdated if you ask me.

Originally Posted by Jamma

I have no idea what cpu I'm using, this is the most technical I'm gonna get.

Than find out...

EDIT:
Just because I'm having a good day: http://www.x264.nl/ <- use the ffdshow binaries from this site (and download the right version - SSE/SSE2 depending on what your CPU can manage)

I am a dolphin, do you want me on your body?

np, but next time be a bit more cooperative. I can't diagnose software problems without some decent informations (and I doubt any developer can).

I was speaking idiomatically.

That's because video decoding is done through ffdshow (CCCP installs that).

I only recommend CCCP because they are the current maintainer of the matroska pack. If you want good matroska support than install that part of CCCP. Otherwise you should try to find a current version of ffdshow (the version included in CCCP is not always up to date).
You'll also get native VC-1 (WMV3/WMV9 called by ms) decoding in ffdshow (not through DMO) when using latest builds. Now that's more a thing for the linux guys, running their system on 64bit native and therefore can't use the DMO loader. And it's pretty fast, compared to the VC-1 reference implementation.

What kind of toxic man-thing is happening now?