I recently ran a Live Event in Microsoft Teams and wanted to get back to the event resources but found my calendar was missing as seen above. This was evident on both the desktop and web interface.
When I attempted to use the link from the Live Event appointment in the calendar in my Outlook I was greeted with the above message:
Unable to connect to your Exchange calendar at the moment
I thought this strange as i had scheduled the Live Event using the calendar icon in Teams?
Turns out that what I had done in the meantime was disable Exchange Web Services (EWS) in my environment. Doing so affects a number of services in my environment including Teams and Exchange Add-ins as it turns out.
If you are seeing the same issues you can use PowerShell to check the EWS status of your environment. You’ll firstly need to connect to Exchange Online with PowerShell which you can do using my script:
then run the following command to see what the EWS settings are at the tenant level:
Get-organizationconfig | fl ews*
to which you should see something like:
From what I understand you’ll need to ensure that EWSEnabled and EWSAllowOutlook are NOT False (i.e. disabled). This will take care of allowing EWS for any new mailboxes created from this point forward.
Also run the command:
Get-CASMailbox | fl identity, ews*
which should result in a list of all the EWS for each user like so:
Make sure that users do not have EwsEnabled or EwsAllowOutlook set to False (i.e. disabled). If it is you can use the command:
set-casmailbox –identity firstname.lastname@example.org –ewsenabled $true –ewsallowoutlook $true
command to re-enable it and set it to True.
If you change an EWS setting for an individual mailbox it can take 4 – 24 hours for that change to flow through according to documentation I’ve seen. In my case however, I found by logging out and back in the change appeared almost immediately.
It should then re-appear in Teams as shown above. If it doesn’t, simply use the three dots (ellipse) at the bottom of the list to add it back in. You may also need to right mouse click it once you have added it back in and “pin” it to the side menu, so it stays there.
So in a nutshell, don’t disable EWS in your environment because things like Microsoft Teams needs it! If you are missing your calendar in Microsoft Teams or have issues with Outlook Add-ins, check EWS is enabled.