Check SBCGlobal server status-
As we all know, SBCGlobal email is an association of AT&T email. So if the AT&T server is down you might face SBCGlobal email sign in problem.
So before the update in your account settings, first you must check the server status. If they are displaying the server is down. I will advise you wait a few minutes or second and then you should try to log in again.
If at&t server status if up, but still occur the same problem. In that condition, you need to follow the steps given below.
You can check the server status of SBCGlobal- Is server down or up today?
Invalid Username or Password-
Another reason for SBCGlobal email log in problem is the wrong email address or password. Ensure that you are typing correct username and password for your email? Because of most of the time, users are typing the incorrect password.
If you have any confusion in typing the username and password or you are getting the wrong username or password error message. In that condition, you should try to reset the username and password for your SBCglobal email settings account first, then you should try to sign in again.
Important links - SBCglobal mail settings | SBCglobal net email login