Q: Cannot sign in to AOL email after upgrading to El Capitan OS

Thanks, this worked for me!  Fingers crossed that it remains OK!

This solved my problem, and was a quick fix...  Thanks

Deleting  AOL and reinstalling it solved the problem for me on my Mac.

This fixed it for me - thanks!

I've now had to delete my AOL account 3 times, because it will start working, then stop, and then I delete and it comes back, and now I'm on round 3.  The amazing thing is it is working with the wrong password.  When I encountered the problem the first time, one of my solutions was to try and change the port settings and password with AOL to try and get it to work.  To log into Aol webmail, it's one password.. to retrieve it on my mac, is a different password.  This is just AFU.

Thank you!!

Thank you, This worked for me!

After upgrading to El Capitan two days ago, I have had many problems with Mail. I have five email accounts, one on Gmail, one on Yahoo, and three more on two hosted mail servers. These accounts were working before the upgrade. After the upgrade, only the Gmail and Yahoo accounts work, the others will not come on line. I tried deleting and re-creating the failed accounts. One worked for a day and the other two would not install due to "verification" issues. The problems with Mail acting up with each OS upgrade is a recurring issue and Apple is irresponsible. One of my computers was running Airmail before the upgrade with the same mail accounts and continued to function flawlessly after the upgrade with no required tinkering with Airmail. I am tired of wasting time and neurons with Mail and have switched the remaining two Macs to Airmail. Apple should not have continuing problems with a basic program like Mail.

Thanks dealmaker - that fixed it!  (Going through Mail, Preferences, Account Information and saving the new password.)

It worked: Mail - Preferences - Accounts - AOL, put in the password, click on Advanced, click off Automatically Detect and Maintain Account Settings, Click SAVE, X out, close Mail Program, reopen, go back to Mail - Preferences - Accounts - AOL, check to be sure the password is still there. If it isn't put it in again - Click on Advanced and put an x back into the Automatically Detect and Maintain Account Settings, SAVE and it worked. I had to do it twice though.

Thank you. It worked: Mail - Preferences - Accounts - AOL, put in the password, click on Advanced, click off Automatically Detect and Maintain Account Settings, Click SAVE, X out, close Mail Program, reopen, go back to Mail - Preferences - Accounts - AOL, check to be sure the password is still there. If it isn't put it in again - Click on Advanced and put an x back into the Automatically Detect and Maintain Account Settings, SAVE and it worked. I had to do it twice though.

I found this thread over MacRumors and the solution worked for me. 

http://forums.macrumors.com/threads/cant-log-into-aol-using-messages.1650353/

I removed my AOL account and re-added it, BUT...

When going into System Preferences > Internet Accounts, instead of using the AOL button, I scrolled down to "Add Other Account".  I added my AOL account that way and it seems to have worked.

I was having the exact same problem, and your solution worked perfectly. Thank you!

THANKS so much, worked perfectly

Thank You - finally - this solved my problem!!!