Connect to PowerShell: Connecting to remote server outlook.office365.com

[mrit]

I have a case open with support but I would appreciate any thoughts or assistance from the community.

Case #05038587
Veeam version: 5.0.3.1033 Community Edition

Whilst trying to add a new O365 organization I am running into issues on the last connection, PowerShell. Connecting to SharePoint and Teams was fine, EWS took some configuration changes but is now successfull but no matter what I try I can not get it to connect to PowerShell. Here is what I've done and checked so far. I'm setting up the org using modern authentication with legacy protocols.

I'm using a certificate instead of an app secret.
The Veeam O365 service account has MFA enabled.
It is excluded from the conditional access policy that disables legacy authentication.
It has an MFA app password configured
It has the following Azure roles, Global Administrator, Teams Administrator, SharePoint Administrator and Exchange Administrator.
I have created and assigned an Exchange authentication policy that permits the use of the following basic authentication methods AllowBasicAuthPowerShell, AllowBasicAuthWebServices
The Azure AD app registration has the folllowing Exchange API permissions configured, EWS.AccessAsUser.All and full_access_app
The Veeam O365 service account has is a member of the ExchangeServiceAdmins role which provides it with the necessary role permissions such as ApplicationImpersonation, View-Only Configuration and View-Only Recipients.

What am I missing?!

[mrit]

edit
I should have added, I can successfull connect to Exchange Online via PowerShell using the service account outside of Veeam but on the server it's installed on, so that isolates firewall and/or permissions I would have thought.

[Polina]

Hi Myles,

Can you also check if the LegacyAuthProtocolsEnabled is set to true?

[mrit]

Hey that's on the SharePoint side yes? Just confirmed that is enabled
LegacyAuthProtocolsEnabled : True

[EarlSinclair]

Hi mrit,

have you fixed the problem? I´ve still the same problem.

[Mildur]

Hi EarlSinclair

Have a look at @regnors Blog in the community boards.
Microsoft has started to disable Basic Auth without asking the customer.

Regnor writes about a way to find out if you are affected by this change and what you can do to get back Basic Auth for Powershell.

https://community.veeam.com/blogs-and-p ... tocol-1805