ERROR: The product distribution file could not be verified.

Thanks Niss+

Confirmed. Worked for me too.One sidenote. After I downloaded the 10.6.6 combo updater, it would fail while trying to install files. After several attempts and some searching on other threads, I did a DiskUtil repair permissions, removed an attached USB drive, and booted in Safe Mode. While in that condition, the updater worked. Then using the App Store started to work too.Thanks.

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