Office 365 Outlook prompts for password

We have a deployment of Office 365 with ADConnect SSO enabled. Additionally, with the implementation of modern authentication (MA) we have set the flag to true. https://support.office.com/en-gb/article/enable-or-disable-modern-authentication-in-exchange-online-58018196-f918-49cd-8238-56f57f38d662

We also enabled MA for Skype online even though we do not use it fully currently.

https://social.technet.microsoft.com/wiki/contents/articles/34339.skype-for-business-online-enable-your-tenant-for-modern-authentication.aspx

More info on Modern Authentication:

https://support.office.com/en-us/article/using-office-365-modern-authentication-with-office-clients-776c0036-66fd-41cb-8928-5495c0f9168a

We started seeing issues where Outlook would prompt for password, especially after password change. After much searching we found the following reg key that is recommended by MS when MA is utilized in order to force outlook to use MA.

https://support.microsoft.com/en-us/help/3126599/outlook-prompts-for-password-when-modern-authentication-is-enabled

https://support.microsoft.com/en-us/help/4041439/modern-authentication-configuration-requirements-for-transition-from-o

We deployed the keys with GPO Preferences.

Outlook:

HKEY_CURRENT_USER\Software\Microsoft\Exchange\AlwaysUseMSOAuthForAutoDiscover

Dword: 1

Skype for Business:

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\16.0\Lync\ AllowAdalForNonLyncIndependentOfLync

Dword: 1


Update: 
We've had a few users where this issue started again. 
Settings - Accounts - Access Work or School - select user - disconnect.  Fixes every time, instantly so far.

Windows 10 Fall Creators Update 1709 fails to apply (update 1803 I experienced same issue)

I recently had a number of Dell Latitude e7450 laptops that would rollback the installation of 1709. I also had several of the exact same model laptop that installed successfully.
In most cases I would be left with no indication of why it failed. I attempted installation from WSUS, Windows Update Assistant, and Windows Media Creation to USB.

I updated drivers, bios, all applications, removed AV (note had most succeed with AV), repair windows update, rename the softwaredistribution folder, etc, all to no effect.

Only when using the Windows Media Creation tool and then running the update from USB did it give me any workable indication of what was going wrong. (double click setup from the USB drive)

"We couldn't install Windows 10.  We've set your PC back to the way it was right before you started installing.  0x8007042B - 0x3000D  The installation failed in the FIRST_BOOT phase with an error during MIGRATE_DATA operation"

That helps! MS even gives a "click here" for troubleshooting codes that pertain. Unfortunately, none of them are this code.  Google foo gave some info and short time later I was looking at the C:\Windows\Panther\  folder.  In particular the C:\Windows\Panther\NewOs\Panther\setuperr.log.

Almost at the very bottom I found a line stating:
Error WRITE, 0x000000B7 while gathering/applying object: File, C:\Users\username\AppData\Roaming\Microsoft\Windows\Recent [2017_09_1_3177.pdf.lnk]. Will return 0[gle=0x00000002]
Error 183 while applying object C:\Users\username\AppData\Roaming\Microsoft\Windows\Recent [2017_09_1_3177.pdf.lnk]. Shell application requested abort[gle=0x00000002]
Abandoning apply due to error for object: C:\Users\username\AppData\Roaming\Microsoft\Windows\Recent [2017_09_1_3177.pdf.lnk][gle=0x00000002]
Apply failed. Last error: 0x00000000

The recent folder under AppData\Roaming\Microsoft\Windows ended up being the issue for every computer that I had issues updating to 1709 or 1803!


Cleanup profile:
I went to the path in question and dumped the entire recent folder.  Started upgrade again and success!
What a pain, why can't the error descriptions be descriptive and helpful.