I recommend you to just uninstall the 5.1.x version that you have installed and to download and install the new version 5.2.0 at the bottom of the post.It has many new features thatdoesn’t come with the update
An update is available for version 5.1.0 of the codec pack that upgrades it to version 5.2.0. The update pack includes newer versions of ffdshow,MediaInfo, and the Codec Tweak Tool.
Update packs for the KLite Codec Pack
KLCP gets updated frequently. However, there may be worthwhile updates to some of the included components inbetween releases of KLCP. The update pack below can be used to keep your current installation uptodate.
KLite Codec Pack 5.1.x (Mega/Full/Standard/Basic/Corporate)
Changelog:
*Updated ffdshow to revision 3096
* Updated Gabest MPEG splitter to version 1.3.1290.0
* Updated MediaInfo Lite to version 0.7.22
* Updated Codec tweak Tool to version3.1.2
File size is 5.32 MB
Do not worry about the other file in the download file(it’s there so I can exceed the 5 MB)
The KLite Mega Codec Pack combines the contents of these twopacks:
* KLite Codec Pack Full
* Real Alternative
Compatible with Windows 2000, XP, 2003, Vista, and Windows 7.
Please say thanks if u download.I need to keep the post on thefront page for everyone else.
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http://rapidshare.com/files/293536348/K-lite_update.zip