I have a white macbook running Mountain Lion and, when I run Disk Inventory, I have 477K mail messages taking up 12GB of disk space and 8GB of "mail message part". The path is ~library/mail/V2/POP or ~library/mail/V2/IMAP and the files appear to be mail attachments which I thought deleted automatically when the messages were deleted. If I go into Library, then Mail, there are POP and IMAP folders for each email account and within each of those there are Deleted Messages, Drafts, INBOX and Sent Messages folders. Within the deleted messages folder, there is a folder with a long random string name and "info.plist". Within the random string name folder, there are two folders - Data and Data Rebuild. Where in the heck do I go to delete all these old mail attachments?! When I google this issue, I'm told they delete automatically but my mac seems to be storing them.