If your ATT email is not working today, then it is probably due to the recent partnership of AT&T with Yahoo. 

Yahoo will not support the working of AT&T accounts from now on and you will have to use the official att.net domain to login into your account.

Well, it happened when Yahoo changed their structure a bit and created a new entity called Oath Inc. They released a statement along with the news, which can be accessed on their website.

If you are having AT&T Yahoo email login problems today, then you should use the official web address of AT&T to login into your account.

Here is the procedure to log in to your AT&T email account.

Way to log in to AT&T email Account

• Open the Currently.com on your web browser and then click on the Mail option from the top right corner of the page.
• Now, you will see the login page for the account, enter the correct login credentials, and then hit the Login Button.
  
• This will take you to the inbox page if the username and password combination is correct.

So, this way you can log in to your AT&T account without too much trouble or confusion from Yahoo and AT&T.