January 2017 update: On a fresh installation of macOS Sierra, changing the default mail client was significantly less painful! I launched “Apple Mail” added an account, from “Apple Mail” preferences I was able to simply change the default mail client, this appears to have made the change without issue.
August 2016 update: Please take a look at the comments before embarking on the fix detailed below. In later releases of OSX 10.11 the procedure may be more simple than the steps I took with 10.11.1
Original Article
Intended Audience: Anybody struggling to change the default OSX Mail Client under El Capitan
Resolution:
Go into System Preferences > iCloud – sign out!
Restart your Mac
Launch “Apple Mail” > Preferences > General – Change the default mail client
Exit “Apple Mail”
Sign back into iCloud!
Back Story:
I wanted to quickly share a tweet from Tweetbot to a friend by email, I was surprised when “Apple Mail” launched and asked me to setup an email account, I do not use “Apple Mail” I was using Airmail as my primary email client at the time.
What should have been a quick change of settings turned into a 10 minute battle with El Capitan to change the default mail client!
Googling revealed that I needed to make this change under “Apple Mail” > Preferences, rather than System Preferences. This was not a problem, although I did have to create an account within “Apple Mail” before the preferences pane became accessible. This done, the field that needed changing was obvious, Preferences > General > Default email reader
I made the change, closed “Apple Mail” and tried again!
…
“Apple Mail” launched !?
I tested an email link from a website to check that this was a system wide rather than an issue specific to Tweetbox. “Apple Mail” launched again!
I checked the default mail client setting within “Apple Mail” preferences, it had reset back to “Apple Mail”.
I set the default email reader to be Airmail a second time. Exited “Apple Mail”, then I relaunched Apple Mail but it had returned Apple Mail.
…
This was resolved by signing out of iCloud in System Preferences > iCloud, restarting OSX, after this I was able to change the default email client.
nickjvturner.com 
Thanks a lot for this!
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great!. I have a feeling that Apple has made this on purpose…..
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I’d like to try your solution but this warning popped up with the first step: “If you turn off iCloud Drive, all documents stored in iCloud will be deleted from this Mac. Your documents will still be available on other devices using iCloud.” Should I be concerned with this message?
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Hello,
I do not think you need to be concerned.
I interpret this message to mean, iCloud documents currently on your mac will be deleted, however, when you re-enable iCloud they will sync back down again.
Good luck, let me know how you get on.
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Thanks a lot! you saved me!
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Hi! this problem was solved by me just by going to the default mail app clicking going to “Preferences > General > Default mail reader” instead of just selecting Airmail from the drop down I went to the “Select..” button, this led me to my Applications folder where I manually selected Airmail.
Maybe give this a shot so you don’t have to go through this long work around.
El Capitan 10.11.2
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Did you try to open and close the Preferences panel for 5 or 6 times? You will sadly find that the problem still lives……
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Just been rebuilding my Mac and forgot about this issue until after I had again set up all my photo library. Now have just installed MS Outlook and got to the point where I encountered this same issue with trying to make Outlook the default mail app. I did not want to have to go through the same pain as I did last time when I signed out of iCloud, set default mail client, then signed back in – don’t get me wrong, that DOES work but it causes my entire 30GB photo library to re-upload to iCloud when I sign back in to iCloud.
So this time, I followed tomtominc’s suggestion which worked a treat for me and saved hours of photo re-uploading. Thanks tomtominc!
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Thanks for this – I was having the same issue and this did, indeed, resolve it. One thing to be aware of, however, is that after re-enabling iCloud on my Mac, it proceeded to re-upload my entire photo library – all 30GB of it – to iCloud even though the library was never deleted anywhere. Takes a while and could cause some grief for anyone on a metered connection.
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This one was giving me headache – thanks a alot, I appreciate it.
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Thank you!!!!! This was driving me insane. I hate Apple Mail with an abiding passion!
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Just to echo all the thanks! You saved me. And Apple support sux.
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You are very welcome!
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This can also be fixed by pasting the following line into the Terminal app:
/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -all local,system,user
credit: https://forums.developer.apple.com/thread/14502
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Following the directions here (log out of iCloud, reboot, etc.) did not allow me to set Outlook 2016 as default mail client. The instructions on this link to the Apple developer site did work.
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The method I have outlined here was the method I used with 10.11.1
It is likely that with later versions there is a better way. Thanks for sharing your findings.
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Can confirm that this worked perfectly on my 10.11.5, without needing to restart or logout from iCloud.
Thank you!
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i have opera browser installed on mac (el capitain), However, for some reason the default email programme in mail is set to opera – if I change it back to mail, it defaults to opera every time I open mail. how can I void this happening?
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I think it depends on where the problem is… Corrupt launch services database, or Icloud corruption. I rebuilt LaunchServices first using Onyx, but that did not fix the problem. Then I found this article, and following this article fixed my problem.
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Under Apple Mail the “Preferences” Option is greyed out. Any tips. I am trying to defualt my email to gmail or outlook.
Thanks….
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You must add an account to Mail first.. silly I know.
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Brilliant fix. Worked like a charm. I had spent nearly two hours Googling for a solution.
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I’m glad this post helped.
Thank you for commenting.
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Hi! Thanks for the info.
This solutions worked for me without restart system.
https://forums.developer.apple.com/thread/14502
Cheers. 🙂
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I didn’t need to sign out of iCloud at all. Just changed the default email reader under Mail preferences, then restarted my computer. The restart solidified the change and my chosen email program (CloudMagic for Mac) is now the default every time. Simple.
(Running El Capitan on a 2016 iMac)
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After going through the PAINFUL ordeal of signing out of iCloud and signing back in which requires signin on every device, this didn’t fix the problem. Mailto links STILL open Apple Mail. GRRRR…..
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Hi, I’m sorry to hear you are still facing a problem here.
Which version of OSX are you running?
Did you restart the Mac when signed out?
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Wow, this is a major PiTA! We have over 400 Macs and 750 users and just made the mistake of upgrading to El Capitan and Office 2016 (from 2011). So this is the best anybody has come up with yet??? To “fix” this we have to create accounts on Apple Mail for every user just to change the default mail client? This is absolutely ridiculous!!! There MUST be a way to script this or else I’ll “downgrade” all of our machines back to Mavericks where management was… well… manageable.
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Hey, that does indeed should like an major PiTA. I have not yet updated to Sierra, so I’m not sure if this quirk has been ironed out in the latest OS.
I recently changed my default mail client again, running 10.11.6 I had to go through all this again.
Perhaps AppleScript could automate the process?
Please come back and let me know the outcome.
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Ok, the lsregister command does more than reset mail associations, it resets all associations including custom file associations and the default browser, etc. It’s another real PiTA and definitely not a solution for any organization with more than 4 or 5 Mac clients or users who don’t want/need IT telling them “Move!” while they’re trying to work.
So, I pieced together a script from all the information I could find to automate the process via SSH, Casper, or ARD. Tested on 2 or 3 machines so far and after discovering the big faux paz with lsregister, I’m ready to test it on a larger group.
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The following worked for me. Go to Mail prefs and select Apple Mail as the default mail program. Then SWITCH TO ANOTHER TAB IN MAIL PREFS – Accounts, or Junk Mail – it doesn’t seem to matter what. THEN switch back to General and close Prefs. Your selection will now “stick.” This is working for me under MacOS 10.11.6.
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Yes, this one worked. Switch to Mail 1st – then click on another heading in preference, then back and with to email client of your choice. Then it sticks……
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Spoke too soon. Now it does not work. Still stuck with Entourage – but want to use Airmail…. This is maddening..
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THANK YOU!!! I tried a bunch of other tips, this is the only one that worked.
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Thank you!!! this actually worked
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I have OS 10.10.5 Yosemite and NOTHING works! I have tried them all. Under general in the Apple mail Outlook is already set to default but it always opens Apple Mail! What do I do?! I hate Apple Mail!
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I have not personally experienced this issue on 10.10.5
Have you tried following step by step the procedure outlined in this article?
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