EDIT 9/19/2023: This blog post has received significant update.
In this second part of the Demystifying Hybrid Free/Busy, we will cover troubleshooting of Hybrid Free/Busy scenarios, more specifica...
Updated Sep 19, 2023
Version 16.0
Blog Post
Hi all,
I tried to find out a problem with F/B - Exchange 2016 on-premises users are not able to view the free/busy information of the office 365 users. They have in Outlook 2016 (could not be updated),
I check OWA F12 and error is: System.Net.WebException: The request failed with HTTP status 401: Unauthorized.
I was able to find almost same error in the Microsoft free/busy troubleshooting guide (Index 26) attached below as well: https://anishjohnes.files.wordpress.com/2019/10/fb_errors.fixesv6.pdf
but when i test Test-OAuthConnectivity -Service EWS -TargetUri https://outlook.office365.com/ews/exchange.asmx -Mailbox OnPremises
my exception are:
System.Net.WebException: The request was aborted: The request was canceled. ---> Microsoft.Exchange.Security.OAuth.OAuthTokenRequestFailedException: The trusted issuers contained the followi
ng entries '00000001-0000-0000-c000-000000000000@*'. None of them are configured locally.
Also I check following guide (index 26) check certificate mismatch but i have the same on perm and Azure.
I found solution, I explaind what I did on the forum: https://social.technet.microsoft.com/Forums/en-US/a0bb1d0a-6639-4fdf-92e1-7fa350e47057/exchange-2016-onpremises-users-are-not-able-to-view-calendar-information-of-the-office-365-users?forum=exchangesvrdevelopment
Regards,
Rafal