I have friends who still use sbcglobal email address, so there must be a way to get those messages. Are you able to get in through the Mail button at the upper right on https://currently.att.yahoo.com/ ?

Jscher2000, thanks for your suggestion. Looks like we both may have started with Fire Fox in 2000.

No, clicking on the mail button only brought up my standard email acct., which was once connected to @sbcglobal.net. I need to eliminate that address. When I click on I forgot my code, it will only send the email to the bad address which I can't get into. I replaced my four YO computer and wanted to transfer my links and bookmarks. Until I can finish the set up, which wants me to sign in via the old email address, I can't bring that info into my new Firefox app without the password.

No, clicking on the mail button only brought up my standard email acct., which was once connected to @sbcglobal.net. I need to eliminate that address.

Are you still able to sign in to that account? I realize it's not your preferred account any more, but do you still have access? If not, you may need to create a new Mozilla account using your new address and abandon the old one. Unless you have paid services link to the account, I don't think you would lose anything in the process.