Mail SMTP (outgoing) does not work after Yosemite upgrade

WORKED FOR ME IMMEDIATELY: i just changed my standard DNS to alternative ones (GOOGLE DNS 8.8.8.8 and 8.8.4.4) and my stuck mails went out in the same second! all other solutions mentioned did not work for me. after i installed other mail apps and the problem persisted, i thought it must sit a level deeper. after hours of googling and trying around I AM VERY HAPPY!!!

Changing the DNS (for example to the ones google provides: 8.8.8.8 and 8.4.4.4) worked immediately! Every other solution i tried, did not!

This is quite clearly something that the Yosemite team need to address going fwd. Whether it's Reseting Keychains or DNS's or whatever, point is... before upgrade all was stable, all was fine... after upgrade, something somewhere aint quite right.

Get on it in Apple... there are people here that professionally rely on seamless comms.

PS: how do you reset the keychain?

Thanks a BUNCH! I spent all weekend trying to get my SMTP server to send out emails. I have a non SSL account. I fixed the keychain/text editor as mentioned above in Flemminggitte's response. IN ADDITION, my port settings kept changing on me. I went both to Mail Preferences AND inside the SMTP server list and unchecked the “automatically detect and maintain account settings”.

Good LUCK! Here’s how:

Step 1: change the settings in two places by DESELECTING “automatically detect and maintain account settings”.
Place 1. Mail Pref (Mail/Preferences), deselect “automatically detect and maintain account settings” is unchecked.
Place 2. SMTP server (inside the mail application under Window, Connection Doctor. Which ever server has the red dot, double click on it and change the settings in the SMTP server pref.). deselect “automatically detect and maintain account settings” is unchecked.

STEP 2: fix the keychain/text editor below as mentioned in Flemminggitte's email.

Look at my reply to Flemminggitts response above. Try changing the SMTP settings in 2 places. This was the lifesaver for me (in addition to Flemminggitts solution). Good luck!

Also have a look in your account preferences that automatically monitors the administration of the account. This is new. Turn that off to see if it changes anything. It's a check box.

Cheers

Correction. I can now send out via my hotmail account but not my cox account. I applied all the same changes to each account. Not sure why one is working and the other is not. Also changed my DNS this morning. That didn't fix it.

This worked! Many many thanks!!!!!!

What worked? More than one suggestion in this 6-page thread.

OK WOW THANKS YOSEMITE. After a couple hours of adjusting this is what worked for me.

• Delete all accounts from mail
• Delete saved passwords in Applications> Utilities keychain>Keychain access

If your email (gmail) requires 'Application-specific Password'. You must access your account settings from your browser before adding into Mail.

Now follow these tips from the HelicopterJon

Open up Finder

In the Finder menu bar select Go > Go to folder

type in ~/Library and click Go (on my kb the "~" is next to the left shift key)

Open the folder Mail

Open the folder V2

Open the folder MailData

Double click to open Accounts.plist (should open in TextEdit)

Find the block of data that contains the offending mail account

Find the line within this block that says <key>UserAllowsInsecureAuthentication</key>

Change the line below this from <false/> to <true/>

Quit TextEdit

Restart mail

Now, open mail and add your accounts. Test by sending a new message, if you try a previous save draft, It will not work.

Click the link - in response to flemminggitte

but this is what worked -

Open up Finder

In the Finder menu bar select Go > Go to folder

type in ~/Library and click Go (on my kb the "~" is next to the left shift key)

Open the folder Mail

Open the folder V2

Open the folder MailData

Double click to open Accounts.plist (should open in TextEdit)

Find the block of data that contains the offending mail account

Find the line within this block that says <key>UserAllowsInsecureAuthentication</key>

Change the line below this from <false/> to <true/>

Quit TextEdit

Restart mail

Chaps/chappesses

For those who still have issues after trying the previous... check to make sure you don't have a 3rd party mail plug-in. Uninstall it if you do.

Go to disk utility and verify 'disk permissions', then 'repair disk permissions'. The last step was to clear the ACL's... (suggest contacting apple support for this).

This solution worked for me. Thanks! Oddly enough, I had no problems the first week Yosemite was installed. Mail worked fine. Then all of a sudden yesterday, it sent everything to the Outbox, regardless of the mail account I was using.

For those that have not found it yet,

The

type in ~/Library and click Go (on my kb the "~" is next to the left shift key)

Is redundant

When you Click on the "Go" menu hold down the "OPTION" key and the Library folder selection will be inserted into the menu list

I had the same thing happen to me worked for a few days and then just stopped. Unfortunately I can only get one of my accounts to work with the solutions. My cox account won't send email. I have tried all the solutions. Nothing works.