Q: Mail App keep crashing after install El Capitan

Thank you BartoloTX! That fixed the problem. (Although the Exchange account I have in Mail won't work. When I enable that account, Mail crashes again. But Gmail and other accounts work just fine!)

This worked for me, thank you!

When is Apple going to get their act together and fix these Mail bugs. What a joke.

I wasted 5 hours of my day trying to get Migration and Mail to work with my new MBP.

The answer is - wait until Apple fixes the bug in their mail application.

In the meantime use your iPhone for e-mail.

Everything worked great until I installed El Capitan.

In a long tech support with my internet provider - I had to disable, then enable multiple accounts.

The new mail app apparently does not allow changing the incoming server to an account. My internet provider had changed outgoing servers long ago. The prior MAC OS apparently still was able to receive messages, but not with the El Capitan switch - but I was able to keep the old accounts enabled to reference the e-mail in them. Then I had to create new mail boxes for the same addresses with the new incoming server name.

Mail worked pretty good for a few weeks, sometimes getting lost and asking what outgoing mail server to use, and now will crash in the middle of creating mail.

Seems like Apple would have enough money to be able to hire some people that knew how to make a rock solid mail app.

This also worked for me but my longest standing email account - an AOL account - is the one that still keeps crashing it.  I will slim down the old messages (about 7000 in total) and occasionally try again to enable it.  In the meantime I just run it independently of Apple Mail. 

The weird thing is that the same mail account doesn't cause this problem on my Mid 2012 MacBook Pro that I upgraded to El Capitan 4 weeks ago.  It is my mid 2011 iMac 27" that is having the issue with that mailbox.

Thanks for the tip - the others I had read elsewhere were scarily long and complex.  This worked like a dream.

Hi, so none of the options in the thread worked for me, including deleting and setting up the accounts again.

But what did was deleting the offending Gmail account from Internet Accounts, and setting it up again NOT using the Google option, but using the Mail account option (so click on add another account, and click on Mail account).  There is a bit of a faff with IMAP and SMTP settings but this information is easily available with a quick google search.

Then everything worked perfectly.  At least for now...

Hope this is of assistance for someone.  I'd been pulling what little hair I have left out to find this solution.

I found a VERY SIMPLE solution for my Mac Mail latency and crash issues.

My steps:

1) I went to my Library/Mail folder and saw that there were both a "V2" and "V3" folder.
    (Note: these files are hidden, so I went to the Finder menu at the top of my screen and selected Go/Go to Folder and put in Library)

2) I made sure my Mac Mail was already closed.

3) I moved the "V2" folder to the trash...but DID NOT empty the trash...just in case...

                                                      ***Disclaimer***

I am not a programmer or computer genius, but have user for Macs for 20+ years. Please back up anything that you might have concerns about prior to trying this. This type of trick recently worked on some of my Adobe Creative Cloud Aps that kept crashing (multiple versions in preferences)...since the "symptoms" for my Mac Mail seemed similar, I decided to give it a try.

It bears repeating that for my own Mac Mail "safety", I only moved the V2 folder to trash, in case I needed to restore it.

Hope this helps someone avoid having to do some of the more complicated steps!

Same experience, crashing on launch, post with Snow Leopard to EL CAP upgrade, started when I began to change the MAIL.app fonts in the app preferences.

I believe I Solved it by running ONYX app which is free, I used this to reset system fonts. Requires a restart but everything worked.

Maybe a cold restart without resorting to Onyx would have solved it but I'll never know as it's working and that's that!

Do have a backup of your system before you run ONYX.

Thanks. It worked

I realized that my Apple ID was also what I'd signed into iCloud with, which I think messed up Mail. Once I logged out of iCloud with that ID and logged on again with my iCloud ID Mail has been working fine. Sorry, I don't explain computer stuff well.  This is the thread that helped me realize what happened...

How to change Apple ID on iCloud drive

This is a rediculous issue....I thought my Ram was bad!(early 08' iMac) My mail caught me in a loop of crashing at reboot repeatedly....I saw that it hadn't refreshed for a day so I finally was able to force quit....tried to open it again and man!, it slowed everything to a crawl, like a virus on a pc.....I'm keeping it off for now...I do have a gmail account configured as well as a yahoo account....

Are you kidding me? This fix sounds like a royal hassle. There has to be an easier way. Hey, Apple please fix this problem so your customers don't have to. It's your job not ours.

BartoloTX 's solution worked for me. There may be 1 account that is causing problems (mail.com) so I haven't tried to enable it a 2nd time because the first time it caused a crash. The rest of my many email accounts are fine.

Great post and thank you so much.

This has been a most frustrating glitch with the native Mail App and has been bugging me for weeks!

I'm so relieved. I found this thread very helpful. But I wanted to update with my own experience as I had the same crashing issue. Nothing worked that was said here accept one thing. I even made every email inactive and still crashing. Problem was the email I actually had just sent. So no matter what it would crash.  Until I actually unplugged the Ethernet. Stayed open and I could go into my outgoing and delete it manually, then make the emails active again.

Whew. I was kinda not looking forward to maybe weeks of checking emails via my web sites and having to sift through spam etc .etc.

Thank you!!

I am using El Capitan 10.11.6 on a MacMini desktop that is cable connected to my ISP.  I had Mail automatically open on startup (System Preferences>Users and Groups>Login Items). For some time now Mail has frozen after opening. I found that if I Quit Mail and restarted it I had no problem.  My fix is to remove Mail from the automatic startup option and then open it manually.