Resolving Mail Problems After OS X 10.10.4 Update

Some Mac Mail users have discovered that Mail app misbehaves after updating to OS X 10.10.4 (and some with OS X 10.11 El Capitan betas) particularly with Exchange and Gmail accounts, but it can happen with other email provider services as well. Typically the problem manifests in one of a few ways; eMail logins suddenly stall or fail, Mail app fails to check for new email, Mail app fails to send emails, or Mail app just doesn’t do anything at all and will basically hang on launch as a never-ending server connection is attempted but fails to establish.

If the only issue you are experiencing pertains to sending email out of Mail app, then try these two tricks to fix SMTP sending errors in Mail for OS X, that fix continues to work in this situation. On the other hand, if you’re having login errors and problems checking for new email as well as sending, we have another solution which many users report to be successful.

Fix Problematic Mail Account Settings After OS X Updates

1. Open Mail app in OS X, then pull down the “Mail” menu and go to “Preferences”
2. Now go to the “Accounts” tab, and select the email account which the problem is occurring for, then click on the “Advanced” tab
3. Look for the box titled “Automatically detect and maintain account settings”, then do as follows depending on what situation you find:

• If it is unchecked, check it – then relaunch Mail app
• If it is checked, uncheck it, then quit and relaunch Mail app, then go back to the same preference setting and check the box again, then relaunch Mail app yet again

     4. Repeat this process for other email accounts in Mail app if necessary

Yes relaunching and re-checking a box is a little frustrating and can be a little tedious, but it does seem to work to resolve any problems with Mail app, as the automatic detection of mail account settings will adjust server settings to accommodate the Mail app configuration.

If you’ve completed this and OS X Mail app still hangs on launch but does not offer any obvious errors, your next troubleshooting step should be to rebuild the Mailbox as described here, which should resolve that issue.

That should resolve whatever Mail problems have occurred in OS X after installing OS X 10.10.4 or OS X 10.11 El Capitan, but if you continue to encounter trouble, specifically with

SMTP mail accounts, these solutions should do the trick.

Not all users encounter this issue with Mail app after installing an OS X update, and though the reason is unclear, it’s possible the problematic setups had configured an email account some time ago, and could be using legacy settings for a specific mail server. In some situations, you may find the port number or mail server address has changed once the new settings have been detected from the mail server, and the problem will resolve itself accordingly.