I upgraded from Mavericks to Yosemite this morning, and had a very pleasant experience for several hours, when Apple Mail suddenly crashed (Not responding). I tried everything including reinstalling Yosemite, but Apple Mail does NOT OPEN.

I have had upgraded 3 Macs today and the Mac Pro has exactly the same problem. Mail will open for about 10 seconds and crashes without doing anything. Not enough time to see what is happening in the activity window. I think Mail needs to be freshly installed but I am not sure what to do???

Frustrating.....

Having the same problem on a MacBook Air from mid 2012 Upgraded from Maverick.... Mail App opens for a few seconds then crashes.

Worked!!! Thank you!

Since downloading the OS X Yosemite upgrade yesterday Apple Mail isn't working. I think there's a major bug.

It hangs and won't respond. Can't access the Mail menu bar commands to make any changes. It crashes. It isn't displaying email content. And, quite oddly, the message viewer window is doing a "punch through" and revealing what's displayed on the desktop behind it.

I'm on a MacBook Pro (Retina, 15-inch, Mid 2014; 16 GB 1600 MHz DDR3)

Apple Mail started crashing a soon as I had installed Yosemite.

I disabled all accounts except iCloud in System Preferences -> Internet Accounts

Mail launched and didn't crash.

I added GMail accounts one by one, including calendars, contacts etc. Again no crashing.

I quit and relaunched mail. Again no crashing.

I then enabled one of my IMAP accounts with Heart Internet and Apple Mail crashed immediately.

I will pursue this with them.

UPDATE:

I used the advice here http://osxdaily.com/2013/08/01/rebuild-mailbox-reindex-messages-mail-mac-os-x/

Repair & Reindex All Messages in Mail app

You may encounter an alert from Mail app telling you that the mailbox must be repaired, but you can also do this manually. This is particularly helpful if the search functions of the Mail app have become unreliable.

~/Library/Mail/V2/MailData/

• Delete every file that begins with “Envelope Index” (optional but recommended: back up these files to the desktop just in case something goes awry)
• Close the MailData window, then relaunch Mail app to force reindexing

Like rebuilding the mailbox, the reindexing process can also take a while, depending on how large the mailbox is and how much mail is stored on the computer. Be prepared for a lengthy re-indexation if you have tons (thousands+) of messages in Mail app. When finished, try the search or perform the task that you had issues with before and things should be working as usual again.

I have now added one of my IMAP accounts and it seems fine, though Mail Rules do not seem to be working.

Same problem here.

Time Awake Since Boot: 4700 seconds

Application Specific Information:

*** Terminating app due to uncaught exception 'NSObjectInaccessibleException', reason: 'CoreData could not fulfill a fault for '0x1580008b <x-coredata://5BB142CF-4001-4155-AC9B-FB0681E69B5E/ABCDNote/p86>''

abort() called

terminating with uncaught exception of type _NSCoreDataException

--------------------------

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Did not help: reinstalling, deleting files, email, etc...

Solution: Deleting contacts (contact data corruption caused by) :-))

(All of them manually from within the app, and files: User > Library > Application Support > AddressBook)

This article is very useful:

http://www.macissues.com/2014/10/19/fix-mail-crashing-after-upgrading-to-yosemit e/

I got Mail working by following the instructions to disable the third party Mail Add-ons.

Why isn't Apple providing this kind of support?

For me, Mail was consistently crashing within seconds of clicking to open it, following the update to Yosemite.

The suggestion from sai dusho bob @ Oct 19, 2014 12:24 PM fixed the bug for me (shutting down Mail, going to ~/Library/Mail/V2/MailData/, moving/deleting the three files beginning with "Envelope Index", then reopening Mail). The first time I reopened Mail after doing it, Mail crashed again, but the second time I reopened, Mail was fine (except for asking to re-send two 2+-year old messages that it re-placed in the Outbox--probably artifacts that resurfaced from reindexing).

Mail has been up and running a few hours now with no problems. Thanks!

Yes! My mail was crashing every time launched. I was even thinking about to revert to 10.9 or restore from old backup.

The advice from sai dusho bob did the trick. My mail is working as a charm now.

Thank you, you made my day.

This solved all the problem:

Went into system preferences and I then disabled every single mail account apart from Icloud. I then added them all back one by one and it starts working again.

Thank you!!

This worked! Thanks so much!

Did what sai dusho bob mentioned and still didn't work. Then unsynced contacts with iCloud and synced again, now Mail seems to be working correctly.