Q: Failed to start SASL connection

I am still flustered by this problem, and none of my answers are a sufficient solution Sorry about that.

In order to further debug the problem, and remove interference of 9 years of bread-crumbs in my keychain, I started by removing the Google account on my MBP using the "Internet Accounts" dialog. I then proceeded to open the keychains app, and query for all keys involving gmail.com, and remove all keychain entries, local and iCloud, that linked to gmail.com - but not those that were Safari passwords merely using my gmail address as user key. Be very careful, if you try that yourself! I even checked Mail that there were no more Gmail SMTP servers, which have a tendency to hang on even if you remove your Google account.

After that, I proceeded to set up my Google account again. All my iDevices also suddenly wanted me to set up my Gmail account again, too. The remaining problem is as follows: Once I connect to a new network, and start Mail, it cannot synch with Gmail. I often have a similar problem on my iDevices, too. On the MBP I see the following hints in my log file:

2015-05-29 08:22:39.532 sandboxd[290]  ([2339]) Mail(2339) deny mach-lookup com.apple.GSSCred

2015-05-29 08:22:39.567 Mail[2339]      Stream 0x600000307980 is sending an event before being opened

2015-05-29 08:22:40.228 Mail[2339]      {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}

2015-05-29 08:22:40.976 Mail[2339]      Stream 0x6000001174f0 is sending an event before being opened

2015-05-29 08:22:41.093 Mail[2339]      Stream 0x60800011a820 is sending an event before being opened

2015-05-29 08:22:41.221 Mail[2339]      XOAUTH2 requires user

2015-05-29 08:22:41.221 Mail[2339]      Failed to start the SASL connection SASL(-1): generic failure: XOAUTH2 requires user

2015-05-29 08:22:44.708 accountsd[277]  Enter ShareKitAccountEnabler  - didChangeWithType - type=2 for account XXX@XXX.com (A57DA091-ACFB-472B-8ED0-465958D06739).

2015-05-29 08:22:44.709 accountsd[277]  AIDA Notification plugin running

2015-05-29 08:22:44.920 icbaccountsd[2344]      Connection error while checking Apple Internalness. Error: Error Domain=NSCocoaErrorDomain Code=4099 "Couldn’t communicate with a helper application." (The connection to service named com.apple.CrashReporterSupportHelper was invalidated.) UserInfo=0x7fd0db439ed0 {NSDebugDescription=The connection to service named com.apple.CrashReporterSupportHelper was invalidated.}

2015-05-29 08:22:44.982 sandboxd[290]  ([2344]) icbaccountsd(2344) deny mach-lookup com.apple.CrashReporterSupportHelper

2015-05-29 08:22:45.021 Mail[2339]      Stream 0x61000011aee0 is sending an event before being opened

2015-05-29 08:22:46.669 Mail[2339]      No worthy mechs found

2015-05-29 08:22:46.669 Mail[2339]      No worthy mechs found

2015-05-29 08:22:48.233 accountsd[277]  Enter ShareKitAccountEnabler  - didChangeWithType - type=2 for account YYY@gmail.com (DCBD516E-8254-4C6A-AE82-8405EAE0157A).

2015-05-29 08:22:48.233 accountsd[277]  AIDA Notification plugin running

... [repeats] ...

2015-05-29 08:22:53.159 icbaccountsd[2344]      SOSCCThisDeviceIsInCircle SOSCCThisDeviceIsInCircle!! 7

2015-05-29 08:22:53.372 icbaccountsd[2344]      SOSCCThisDeviceIsInCircle SOSCCThisDeviceIsInCircle!! 8

... [interspersed, repeats] ...

where the icbaccountsd message repeats with an increasing number after it. Checking in Mail, there is a user name associated with both, the IMAP and the SMTP account. The "user" that the error message refers to might be something like the consumer key or access token of OAUTH. I'd also like to know, why the sandboxd denies the credential lookup to Mail.

My solution my current quandary is to quit Mail right there, and wait until the dot under the icon went away. Then, after reinvoking Mail, it will then connect with Gmail, no problems. Unfortunately, that does not help when my iDevices hang checking Gmail.

I would blame icloud keychain sharing, but it is too convenient a feature (when it work) to turn it off.

I have tried the solution provided by YasonX related with gmail 2-step verification and run into a more serious problem: Mail is using almost 100% cpu.

In my log there are huge numbers of these messages:

14/06/15 11:12:24,481 accountsd[1465]: AIDA Notification plugin running

These AIDA message stops when I disable in Mail's advanced settings related to the gmail account 'Automatically detect and maintain account settings'.

But then in my log the "Failed to start the SASL connection" reappears.

So I back to the original problem.

Perhaps I have overlooked something?

This is what I did concerning the SASL message problem, and since then, messages in Console have stopped cold:

In addition to unchecking Automatically detect and maintain account settings, as some others have advised, I went into General of Mail preferences and set Check for new messages to Manually. This didn’t seem to affect the reception of mail from Gmail because I still automatically got the test messages that I had sent to myself from different email accounts. Then I went ahead and rechecked Automatically detect and maintain account settings to see what would happen, and still no new error messages. There seems to be a lot of bugs with Mail, but at least I’m no longer annoyed by the constant stream of messages. I’m waiting to see what happens.

I'm uncheck 'Automatically detect account settings' in smtp settings, but after this i still saw SASL error messages from Mail in console. After this, also i uncheck 'Automatically detect account settings' in Advanced tab in General Google Account settings (see screenshots), and now my console Mail messages has clear from SASL error messages!

I tried that (unchecking "Automatically detect and maintain..." for both, IMAP and SMTP). Once I woke the MBP onto a new network from sleep, and started Mail, my logs filled with the SOSCCThisDeviceIsInCircle messages. Worse, my trick of stopping Mail and starting it again didn't even work when the auto detect was unchecked. I'd be interested in your experience, if it works for you across multiple Mail starts on new networks.

Hello, YasonX!

Now i write this post from another network and now my console Mail messages still clear, no SOSCCThisDeviceIsInCircle or any strange error messages.

I'm also do it on MBP, and now i tried disable/enabled Gmail account, restart Mail app, but console is still clear and "Automatically detect and maintain..." has unchecking state.

But i'm unchecking both "Automatically detect and maintain..." settings just yesterday, so i think time for one day is not enough time to test this from your problem.

Otherways, may be you network provider has own some specific settings of Gmail.

Hi AlexS2,

The unsetting of "automatically detect..." setting did never work for me. However, after upgrading to 10.10.4 I don't have this particular Mail problem with GMail any more. Mail now chats nicely with GMail.

Regrettably, after upgrading to 10.10.4 I still see: Failed to start the SASL connection

With the 10.10.4 update, the rules of the game have changed all.

Try this: Using your browser, sign onto your Gmail account. You will be taken through the steps for 2-step verification and given a new password. Follow the instructions, and things may start to work correctly. It did for me. Now I get some other bizarre messages, but that is neither here nor there.

Same here. After update to 10.10.4 and rechecked "Automatically detect and maintain..." not a single error message in any of the five gmail accounts.

confirm. After update to 10.10.4  i'm also recheck "Automatically detect and maintain...", otherwise error 'filed to start SASL Connection' happens again.

With Yosemite 10.10.4 you now want to check this box!