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Sometime during on of my daily cleaning my registry with CCleaner
Problem 1. Don't do that. Follow my signature advice
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I think CCleaner deleted an important registry entry
See Problem 1. . . also CCleaner doesn't delete anything unless you tell it to
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I am currently using Windows 7 RC 64-bit
Problem 2 personally I wouldn't use ANY registry Cleaner on Windows 7 until official world wide release as MANY registry entries are bound to be differently handled in Windows 7 and so it should be properly and completely vetted by Programmers before drastic things like reg cleaning are done
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If you have been keeping the CC backups, they should be saved to "Documents" one by one latest one first, remerge it back to the registry.
If that does not fix the issue it is unlikely a CC problem, try doing a system restore.
My snarkyness (Though absolutely honest and Importantly TRUE) aside this answer is right on the money. If you've been running a {Gasp Ewwww} daily clean and don't have reg backups from those you need NEVER to do a reg clean again.
I don't believe CCleaner did this but. . . see part 3 of my answer.
And for goodness sake read and follow my signature it'll save your life the next time this happens (or the first time as I don't think CCleaner did this)
WHY ARE you doing daily reg fixes