How? What? I don't even... (MASSIVE Apple Mail folder) (AKA Mah mac is outta space!!!!)

I work at a local computer repair shop and from time to time I see something that I still scratch my head at at how often it happens. A customer brought in her machine because it was out of a disk space (200MB out of a 1TB drive). I thought to my self, There is no way this is possible.  Well, it turns out my suspicions were correct. I don't even know how Apple Mail does this, but any time there is a message that gets stuck because either it didn't get sent properly or is somehow incorrectly formated, it will sit there and recover the message OVER AND OVER again till you literally have no room left on your drive.

I go directly to the offending folder (~/Library/Mail/V2/Mailboxes) and what do I find? A HUGE recovered messages folder. I mean, this thing was absolutely stupid in size. It was some 698GB!. Yes, 698GB in size. How or what happens to cause this, I have no idea, but this is stupid. Apple Mail needs to be fixed to stop this idiocy. After removing the affected recovered messages folder along with the mbox.cach file, all is good. It is nice to have these quick fixes, but still, it makes no sense to me that this stuff happens only to Apple Mail (as far as I am aware of). Kind of a shame. I like Apple Mail. 

The best way is to drop down into terminal and navigate to your user profile's Mail folder under your user Library. Then do an ls -lha (list all normal and hidden files in a human readable form). Though the ls command doesn't always do you justice. It doesn't hurt to navigate to it under Finder (just press Shift + Command + G to bring up the go to window and type in ~/Library/Mail/V2). Right click on your mailboxes and look at their sizes. If you see anything stupid in size, check the recovered messages folder. It is big, delete it along with the .mbox.Cache.plist. That will take care of the offending message(s) that are stuck sideways, and save you space on your drive. 

It happens on ALL versions of mail. The recent one I did this for was on Mail for on OSX 10.7.5

For whatever reason a malformed email gets stuck inside of mail and tries to send it, fails, recovers. Then for whatever reason repeats this OVER AND OVER again in a loop. The only way to break the cycle is remove the recovered messages folder and blow away the mbox cache.