Q: Mail hangs since OS x 10.10.3

Launch the Console application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad and start typing the name.

The title of the Console window should be All Messages. If it isn't, select

          SYSTEM LOG QUERIES ▹ All Messages

from the log list on the left. If you don't see that list, select

          View ▹ Show Log List

from the menu bar at the top of the screen.

Click the Clear Display icon in the toolbar. Then take an action that isn't working the way you expect. Select any lines that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.

The log contains a vast amount of information, almost all of which is irrelevant to solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.

Please don't indiscriminately dump thousands of lines from the log into this discussion.

Please don't post screenshots of log messages—post the text.

Some private information, such as your name or email address, may appear in the log. Anonymize before posting.

Please take these steps to resynchronize the iCloud keychain. Your keychain on iCloud and your other Apple devices won't be affected. Take Step 2 only if Step 1 doesn't solve the problem.

Step 1

Back up all data.

Open the iCloud preference pane and uncheck the Keychain box. You'll be prompted to delete the local iCloud keychain. Confirm—the data will remain on the servers. Then re-check the box. Follow one of the procedures described in this support article to set up iCloud Keychain on an additional device. Test.

Step 2

If you still have problems, uncheck the Keychain box again and continue.

Triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination  command-C:

~/Library/Keychains

In the Finder, select

          Go ▹ Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return.

A folder named "Keychains" should open. Inside it is a subfolder with a long name similar to (but not the same as) this:

           421DE5CA-D745-3AC1-91B0-CE5FC0ABA128

The above is only an example; yours will have a different name of the same general form. Drag the subfolder (not the Keychains folder) to the Trash and empty.

Restart the computer and re-enable iCloud Keychain.

Hi, I have been having problems with mail hang since upgrading to the 10.10.3 as well.

Below is the log as instructed by you above:

19/4/15 4:14:21.579 pm com.apple.xpc.launchd[1]: (com.apple.imfoundation.IMRemoteURLConnectionAgent) The _DirtyJetsamMemoryLimit key is not available on this platform.

19/4/15 4:14:22.341 pm discoveryd[77]: Basic DNSResolver UDNS Send(): UDP Sendto() failed to DNSNameServer 8.8.8.8 Port 53 errno 51, fd 60, ErrLogCount 5 ResolverIntf:4

19/4/15 4:14:23.439 pm discoveryd[77]: Basic DNSResolver UDNS Send(): UDP Sendto() failed to DNSNameServer 8.8.8.8 Port 53 errno 51, fd 64, ErrLogCount 6 ResolverIntf:4

19/4/15 4:14:24.542 pm discoveryd[77]: Basic DNSResolver UDNS Send(): UDP Sendto() failed to DNSNameServer 8.8.8.4 Port 53 errno 51, fd 69, ErrLogCount 7 ResolverIntf:4

19/4/15 4:14:25.618 pm discoveryd[77]: Basic DNSResolver UDNS Send(): UDP Sendto() failed to DNSNameServer 8.8.8.4 Port 53 errno 51, fd 60, ErrLogCount 8 ResolverIntf:4

19/4/15 4:14:25.672 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

19/4/15 4:14:25.739 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

19/4/15 4:14:26.251 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

19/4/15 4:14:26.425 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

  19/4/15 4:14:26.581 pm Mail[771]:

...... more ...

19/4/15 4:14:35.382 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

19/4/15 4:14:36.095 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

19/4/15 4:14:36.128 pm Mail[771]: XOAUTH2 requires user

19/4/15 4:14:36.128 pm Mail[771]: Failed to start the SASL connection

SASL(-1): generic failure: XOAUTH2 requires user

19/4/15 4:14:36.295 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

19/4/15 4:14:36.308 pm Mail[771]: XOAUTH2 requires user

19/4/15 4:14:36.308 pm Mail[771]: Failed to start the SASL connection

SASL(-1): generic failure: XOAUTH2 requires user

19/4/15 4:14:36.787 pm Mail[771]: XOAUTH2 requires user

19/4/15 4:14:36.787 pm Mail[771]: Failed to start the SASL connection

SASL(-1): generic failure: XOAUTH2 requires user

19/4/15 4:14:36.811 pm Mail[771]: XOAUTH2 requires user

19/4/15 4:14:36.811 pm Mail[771]: Failed to start the SASL connection

SASL(-1): generic failure: XOAUTH2 requires user

19/4/15 4:14:36.836 pm Mail[771]: XOAUTH2 requires user

19/4/15 4:14:36.839 pm Mail[771]: Failed to start the SASL connection

SASL(-1): generic failure: XOAUTH2 requires user

19/4/15 4:14:36.865 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

19/4/15 4:14:36.903 pm Mail[771]: XOAUTH2 requires user

19/4/15 4:14:36.903 pm Mail[771]: Failed to start the SASL connection

SASL(-1): generic failure: XOAUTH2 requires user

19/4/15 4:14:37.481 pm Mail[771]: {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

Appreciate it if you can provide some suggestion as to how to fix the problem.

Thanks.

Same problems here, since upgrade to 10.10.3

Cleaned up the keychain from all google stuff,

Did delete google account , re-add google account

Problems stil remain on all 3 machines I use to read mail.

Same problem here:

Failed to start the SASL connection

SASL(-1): generic failure: XOAUTH2 requires user

Appears in Consle every few seconds. Mail hangs.

Finally, i got to fix the problem, thanks to the suggest from HugoMe at this post

Failed to start SASL connection

I just unchecked the "automatically detect and preserve accounts settings" option in Mail/ Preferences/ Accounts / Gmail / Advanced

This is the solution.  Bloody Gmail!

Yeah!!!

unticking "automatically detect and maintain accounts settings" option in Mail/ Preferences/ Accounts / Gmail / Advanced" fixed it for me

I upgraded to 10.10.5 and the option "Automatically detect and maintain accounts settings" is greyed out for gmail accounts now. What gives?