I have about 31,300 emails in 4 different inboxes in Mail. Sadly to say, it is extremely slow.
Is there any tips or trips to optimize Mail? And no, I don't want to delete any, I need them for work.
The easiest thing to do is clean up the index file Mail uses to track the messages:
Thanks for this tip to the estimable Brett Terpstra. The linked article explains how to make an AppleScript file to measure things before and after to see if the operation thinned out the size of the file Mail uses to store the pointers to the messages. I would add, quit Mail and make a backup before trying to clean the file. A
Also, this thread probably goes back to @bbum and his weblog-o-mat and perhaps even deeper back...
For me the sqlite3 vacuum didn't speed Mail.app back up.
The thing that returned my Mail.app to blazing fast speeds was deleting the mail sandbox folder.