I am running Outlook Version 1708 (Build 8431.2079) with Exchange Online mailboxes and unable to create a new profile for a mailbox that I have full access to. Here are the steps I am following which have worked fine until the most recent C2R update.
Log into the PC as my account
Go to Mail
Name profile and click OK
Enter email address or upn of the mailbox I want to access
Click connect and it spins for some time then gives the error below
I have a colleague that can reproduce the problem with a different mailbox as well. I can access the mailbox via Outlook web without issue. I notice a new screen for profile creation. Is this a known bug?
Works fine here, but the UI bits are changed now. Try selecting the "manual" step, choose O365 account and when asked for credentials switch to using your (delegate) UPN. I'll put a more detailed article when I get some time...
Oh wait, you meant new profile. I tested by adding the shared mailbox in an existing profile, that part worked fine. Creating a New profile fails indeed, I never get prompted for creds. I tried changing the account type and Outlook then complained about the lack of license, but never asked me for creds...
This appears to be partially fixed. I updated my Office bits to 8431.2094 and I can create a profile from Outlook if I set Outlook to prompt for profile from Control Panel>Mail. If I try to create the profile from Control Panel>Mail it fails.