K-Lite Codec Pack is a collection of codecs, DirectShow filters and tools. Codecs and DirectShow filters are needed for encoding and decoding (playing) audio and video formats. The K-Lite Codec Pack is designed as a user-friendly solution for playing all your movie files. With the K-Lite Codec Pack you should be able to play all the popular audio and video formats and even some rare formats.
This download is for the Full package and contains all the codecs a normal user would ever need.

The K-Lite Codec Pack has a couple of major advantages compared to other codec packs:

It it always very up-to-date with the newest (and/or best) versions of the components.
It is very user-friendly.
The installation is fully customizable, meaning that you are able install exactly those components that you really want.
Uninstallation removes all files and registry entries created by the pack.
It is extremely easy to make a fully customized unattended installation.
It has been very well tested, so that the package doesn't contain any conflicting or buggy codecs.
It tries to avoid potential problems with existing codecs and even fixes some problems. The pack is able to detect broken codecs and filters on your system, and remove them for you.
It is a very complete package, containing everything you need to play your movies.
There are different packages. From small to extra-large.
Suitable for both novice and expert users.

Title: K-Lite Codec Pack 4.42 (Full)
Filename: klcodec442f.exe
File size: 15.05MB (15,781,441 bytes)
Requirements: Windows 2000/XP/2003/Vista/XP64/Vista64
License: Freeware
Date added: December 20, 2008

* Updated Media Player Classic to version 6.4.9.1 rev. 91
* Updated Media Player Classic Homecinema to version 1.2.929.0
* The Homecinema version of MPC is now used by default
* Updated ffdshow to revision 2527
* Updated Matroska splitter (Gabest) to version 1.0.3.1
* Updated MP4 splitter (Gabest) to version 1.0.0.5
* Updated Ogg splitter (Gabest) to version 1.0.0.2
* Updated MPEG splitter (Gabest) to version 1.2.925.0
* Updated Xvid to version 1.2.1
* Updated x264VFW to revision 1042
* Updated MediaInfo Lite to version 0.7.8
* Updated GraphStudio to version 0.3.1.0
* Some compatibility improvements
* Detection of broken codecs/filters now also analyzes 64-bit items