Yahoo and AT&T mail not working on Windows Mobile 10

[Sir Lumia-a-Lot]

I updated to WM10 on Saturday (February 6, 2016). I'm running OS Build 10.0.10586.71 on the Nokia 1520. To make it brief I can't get Yahoo mail or AT&T mail to work at all. I have an AT&T account which uses the crappy pathetic Yahoo email service (so I've tried connecting to both). I have been searching and testing now for three solid days and no one has the answer and neither do I. The automatic setting are worthless. I either get an error code of some kind or it won't sync or it does nothing. I reboot my phone between each setting. I've linked with Outlook mail and it still doesn't help. Yahoo.com has no help. AT&T.com has no help. I've read all the forums, the tech sites and nothing helped. Even the infamous YouTube was of no benefit.
Has anyone been able to install this type of email on their WM10 phones? Any suggestions would be greatly appreciated. I don't want to go back to 8.1 but I have to have this email account on my phone.

Thank you very much.

 

[Chintan Gohel]

My yahoomail account syncs fine although in the beginning, it had issues due to some two factor security setting.

My suggestion would be to remove the account and try adding it again

 

[Sir Lumia-a-Lot]

I've added and deleted the account over and over again. I tried different setting and nothing works. Then, yesterday, for no reason it started working. Just a bug I guess. Thanks for your response.