This will take some time, but it will definitely be worth it. Rebuild the Message Index Databaseĭoes Mail seem to be lagging on tasks that used to be completed in just a second or two? Especially if you have a lot of contacts in your address book or have stored a lot of messages, you can rebuild the Message Index Database to help Mail get back on its feet.
In fact, you should see Mail run faster and more efficiently than before. At worst, you’ll lose the draft of whatever message you were working on when you closed it, but beyond that, there should be no effect on functionality.
However, once you reopen it everything should be back in working order. Give Mail a few moments to be terminated before you relaunch the app.
