Yes! I am having the same problem, but my problem isn't just limited to vista media center, media player has also disappeared. This happened to me last year too before SP1 and I just reinstalled windows. Now with SP1 out, I'm not sure how to go about doing that without losing files. I really don't want to go through the hassle at all though. It disappeared again a few months ago for the second time, but I could never find help online. I even went to get help from Microsoft and they didn't know what the problem was.
For the second time in three months, WMC has spontaneously disappeared. Suddenly the shortcut on my start menu says that the item it refers to has been moved or changed.
This does not coincide with any new installation or system modification.
Last time I fixed it by doing a complete repair install but that involves uninstalling SP1 first, then doing the repair install then reinstalling SP1! An object lesson in how to make something inconvenient even more so.
WMC doesn't appear in c:\program files, nor in control panel\programs and features. Neither does an sfc \scannow restore it.
Can anyone help please?

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