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OSX Disk Space: Save space after Mail upgrade

Good tip:

 

Migrating Mail from Lion to Mountain Lion leaves behind a folder containing previous attachments.

Attachments in Lion were saved to ~/Library/Mail Downloads, but under Mountain Lion, Mail is now sandboxed, and the new path is ~/Library/Containers/com.apple.mail/Data/Library/Mail Downloads.

During the upgrade, the folder contents are copied from the old location to the new, so the old location can be deleted to save some space.

Mac OSX hints:
Save space after Mail upgrade