Did the fresh ML install yesterday and no problems with mail. Today mail crashes at start, obviously tried rebooting. I went into the library and trashed the the mail accounts but it still won't start, it quits as soon as you try and open it. Are there other prefs I can trash to try and get mail open? I didn't see a plist for mail in library preferences, I thought that is where it was. I found the MailAccounts.plist and dumped that but still no go.
Didn't get that far. I was getting ready to run geekbench and decided to check my mail. It was after installing Java however but I don't see how 2012-004 would cause this. 2012-004 installs the correct runtime for ML.
Now I'm taking shots in the dark. I'm using Appdelete to archive everything associated with mail with the exception of mail.app itself just to see. I can always put it back.
I don't remember if I checked my mail after installing XQuartz (since X11 got dropped by Apple). I'll kill that next if this archiving doesn't work.
Hmmm. Archiving the items didn't work. Using Appdelete to DELETE everything except the mail app did. And it didn't delete the mail caches so the accounts are still listed. I'm rebuilding the mailboxes just to make sure everything is there but it's just another WTF moment.
My console also shows addressbook datafile is a directory. I tried deleting all my addressbook contacts but it still doesn't start.
If reading correctly it looks like an AddressBook filelock operation triggered the problem. Wild guess, maybe you just need to fix permissions of AddressBook directories and/or (under ~/Library/Application Support/). It could be something else though... Keep in mind Disk Utility repair permissions may not help as the problem appears to be with your AddressBook files.