I'm having the same problem with an IMAP account on the new Surface Duo, using Outlook. It works, then periodically, it stops working and asks me for the password again. Entering it again sometimes works,. Sometimes, I have to delete the account and set
it up again. All the while, my Exchange mail account keeps humming asking perfectly fine. Yahoo asking works too, though the same thing did happen to the Yahoo account once. Outlook Mobile support, accessed via the app, has been unhelpful. Here's where
we stand after many messages back and forth.
Me:
Let's be sure we understand each other. This IMAP Sprynet account does not have dual authentication. It only uses a password. The server does not cause any of the following to applications to re-challenge me for a password, ever: Outlook 2016 for Windows,
Apple's Mail in IOS, Google's Mail in Android, Microsoft's Mail in Windows Mobile on Microsoft's Lumia 950. You are saying that the server is asking Outlook Mobile to re-challenge me for password, that it is not Outlook Mobile's failure to retain the password?
Microsoft Outlook Mobile Support Agent:
Hi, this is exactly what Im' saying, the Server ask Outlook Mobile for the password.
Thank you
Does that make any sense to yo ? Doesn't an email server always seek authentication? And, if no other email client on any other device has a problem, if it's only the Outlook App on an Android device, don't you think it's a problem with Outlook?
Just for kicks, I've setup the account on Outlook in iOS, to see if the problem manifests itself there, though I haven't found any reported problems for Outlook on IOS.