Login problems with all email apps

I can't get any of my email apps to work with my email accounts anymore. I have tried Windows Mail and then Blue Mail and now Thunderbird and always get the same runaround - Can't recognize the login and password - maybe reset password-uh oh something is wrong -don't recognize that login and password yada yada yada. I have reset my password over 50 times this year and am ready to call it quits with AT&T and Yahoo. Someone needs to fix Yahoo because I am obviously not the only person having problems with their email. Hmm Xfinity is starting to look good right now.