troubleshooting Question

Microsoft Exchange

Avatar of Sal Qamar
Sal QamarFlag for United Kingdom of Great Britain and Northern Ireland asked on
MicrosoftExchangeOutlookMicrosoft 365
8 Comments1 Solution65 ViewsLast Modified:
Hi, We have an issue which has started in the past week or so where we cannot open up any additional Office 365 mailboxes in Outlook that we have given permission to (rights given prior to the past week are working fine). In our Office 365 tenant we have three domains, (primary), and I ran a test giving myself access to one of each suffix and only the one works, the other two give an error:

This the same in and out of cached mode and is the same for all users that we have tried. It is the same in OWA. If I check the Connection Status in Outlook a connection is not even being tried. Our setup is Exchange 2013 CU19 hybrid with Office 365 tenant, Microsoft 365 Apps client.

Please assist with a solution. 
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