Outlook 2016 doesn't accept password or app password

Most average users don't even know where to start to address these issues. By the posts here, most of the commenters are technically savvy, and have knowledgeable and purposeful configuration of their own devices and email clients - we know what we are doing...

Issue started on 1/23 afternoon US Pacific, the evening before I started an oversea business trip. After I completed my almost 3-week trip, the issue is still not yet resolved, yet Microsoft refuse to rollback whatever they broke. Most of my non-technical friends and relatives that use Outlook.com/Hotmail/MSN/Live mail with a EAS client are having this issue once I pointed out the problem and symptoms. Almost 3+ weeks of this, people start to realize they missed newly added meetings or tasks, and didn't get emails until many hours after the fact - all because of this issue.

Another problem that hasn't been talked about is that, at least for Outlook desktop, the password prompt dialog is drawn on top of all other screen elements, plus it will throw a Windows notification. Every time this password event prompt dialog shows up, it's incredibly disruptive to your workflow because it suddenly takes the cursor/mouse focus away from whatever you are working on. For mobile clients, this event causes a notification to be shown as well, so you getting constant alerts, chirps and/or vibrations.

I really don't understand why Microsoft won't roll back the changes on the production system, and continue to work on debugging the problem separately for later deployment.

Hi all,

I got the Known Issue updated to reflect the issue is still being worked on, Outlook and other apps are unable to connect to Outlook.com - Microsoft Support. The main thing happening now is I have contacted multiple people in this forum thread and provided their account info to the service team. The service team is investigating the connectivity for those accounts and making ongoing changes. There is representation for all the connection types e.g. EAS, POP, IMAP, Exchange, and both desktop and mobile apps. Once I know any status updates I will post back.

The issue is DEFINITELY NOT RESOLVED! MS jumped the gun again.

The issue most manifested when your client syncs with the server either as a push or at timed sync interval. This issue was fixed or largely improved in the last day or two.

However, if your client attempts to send an email, mark an email, change attribute on the email, move an email, or otherwise need to initiate a create or change request asynchronously to the server, then you will see the same error prompt. I can literally reproduce this on command.

Therefore, the issue is not fully resolved as MS claims.

Same issue in Outlook 2013 too.

A few more impacted users here too:
Outlook 2013 will not retain password for my hotmail account - Microsoft Community

9Folders seems to have hijacked this thread. There are many of us who use a wide range of e-mail clients on a wide range of devices from phones to desktop computers that are experiencing this issue, and it is not helpful to the rest of us if a false sense of resolution has been made regarding this issue only because one developer decided to create a workaround for a known Microsoft issue that is not working with IMAP/SMTP industry standards.

We use Thunderbird, Outlook 2016, and the Samsung Email apps and am constantly, intermittently bombarded with errors pertaining to credentials. On PCs we resubmit the same username / app password credentials and it is eventually accepted and syncs a few folders until another intermittent error is experienced.

This is affecting all our Outlook accounts: *hotmail.com, *live.ca, *live.com . This issue does not affect any Gmail accounts with any clients we use on any device, which indicates that it is not a client developer issue but a Microsoft issue that is not following standards.

This all started about 6 days ago after years with no issues, and is incredibly frustrating because it impacts our business and productivity.

Thank you.

https://www.reddit.com/r/Outlook/comments/19ed5tx/cant_log_in/

https://www.reddit.com/r/exchangeserver/comments/19e1qgc/help_wios_173_suddenly_asking_for_password_and/

https://www.reddit.com/r/Outlook/comments/19dx64p/outlook_2013_windows_10_suddenly_not_accepting/

https://support.microsoft.com/en-us/office/pop-imap-and-smtp-settings-for-outlook-com-d088b986-291d-42b8-9564-9c414e2aa040

https://support.microsoft.com/en-us/office/outlook-and-other-apps-are-unable-to-connect-to-outlook-com-f4202ebf-89c6-4a8a-bec3-3d60cf7deaef

https://support.microsoft.com/en-us/office/fixes-or-workarounds-for-recent-issues-in-outlook-for-pc-ecf61305-f84f-4e13-bb73-95a214ac1230

https://answers.microsoft.com/en-us/outlook_com/forum/all/outlook-2016-doesnt-accept-password-or-app/b806e4e8-28fd-4b5b-8be2-2b03cf39b938

https://answers.microsoft.com/en-us/outlook_com/forum/outlk_win-outtop_classic-outsub_ofh/outlook-2013-will-not-retain-password-for-my/61d16c93-64b3-469f-8863-5c2d41e8885b

https://www.bleepingcomputer.com/news/microsoft/microsoft-says-outlook-apps-cant-connect-to-outlookcom/