Tweak MCE was a PowerToy released for Media Center 2005 which allowed access to certain settings which are not exposed in the Media Center UI, and otherwise would require manual registry editing to modify. When Update Rollup 2 came out the existing version of Tweak MCE did not recognise it as a supported version of Media Center since the version number changed from v3.0/v3.1 (Update Rollup 1) to v4.0. In addition to supporting Rollup 2 there are a few extra options included in this version for some of the new features such as My DVDs and overscan.
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