Apple has released an update to the Mail app in OS X Mavericks to fix compatibility issues with Gmail and improve stability. Shortly after the latest version of OS X was released last month, Mavericks users complained that moving Gmail messages around in Mail no longer worked properly.
Users can find the update in the Mac App Store, or download and install it manually. Apple recommends that you back up your system before going through the process.
See also: Review: OS X Mavericks
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