Want to Speed Up Apple Mail?

It’s really easy:

1) Close mail

 

2) Using Terminal run this command:

sqlite3 ~/Library/Mail/V2/MailData/Envelope\ Index vacuum;

3) Move the following file somewhere else or delete it (I moved it in case :-) ):

 

~/Library/Containers/com.apple.mail

 

4) You are done restart mail and all good.

Of course do a backup before doing all this.

Courtesy https://discussions.apple.com/people/Incito%20Networks from https://discussions.apple.com/thread/4658459?start=0&tstart=0