How To: Fix “Error 100″ in the Mac App Store

Many users, have had the release of the Mac App Store this morning blighted by the message "We could not complete your App Store request. An unknown error occurred (100)."

What you’ll need to do is download an app — any app — in the App Store via iTunes, or one of your Apple devices with access to the App Store. Doing so will trigger the new iTunes Terms and Conditions to appear. They are, for some reason, failing to pop up for some users when they try to download an app in the Mac App Store. Then you’ll need to restart your computer and reopen the Mac App Store. (Some users say they merely had to restart the Mac Store or iTunes to get it work, but I had to restart my computer.) You should be able to download apps in the Mac App Store immediately afterward.

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