Scan to Email and folder stopped working after problems with Microsoft Modern Auth

[RCB-Houston]

This org had to do a workaround to get access to Outlook email due to the modern auth not being setup for MAPI (we think.... Microsoft is still working on the problem) in the meantime, a registry edit allows them to continue using Outlook in basic auth, but scan to email as well as scan to folder (important business processes for this org) have stopped. Is there some way to verify what is preventing the scans from being completed. The error log has very limited details.

[RCB-Houston]

It also seems incoming FAXes are being rejected also.

[Repairatrooper]

Is this an on-premise exchange server or hosted Office365? Microsoft announced major changes to security months ago and the switch was flipped at the beginning of October. Customers who had already modified their account to work with existing hardware were supposed to be grandfathered and should still function. You option is you may need to find a SMTP service that will allow for sending without using modern authentication. 

Your statement that fax does not work provides no information at all. Does the fax modem respond at all when a call is coming in? Is the device configured to forward faxes to an email or folder location? Can the client send faxes out still? Is the line working, are you able to call it with a normal phone?  

In some cases where multiple problems seem to be unresolvable, performing a partial clean on the system and re-entering data seems to resolve the problem. Keep in mine that these systems are running on a Windows OS core so they can have the same long term loss of function just like a PC.

[RCB-Houston]

This is Exchange Online, but with on-premises AD synced with Azure AD.

Using a different SMTP service might be needed (although it shouldn't be needed), so thanks for that idea.

Our troubleshooting has been focused on the scanning issues, so all that we've heard is that the FAX isn't working, but I know no further details at this point. I'm sure that'll become clearer as this goes on.