Exchange Online room resource available but booking fails

Question

Exchange Online room resource appears available when scheduling a meeting but after booking the room shows as "in use" or "not available" for all users in the tenant

Answer 1

Hi @Fabian

Thank you for posting your question in Microsoft Q&A.  

I understand that you are encountering an issue where the room resource is not showing the correct availability. 

To better understand and resolve the issue, could you please help provide the following information: 

Does this behavior affect one specific room or all meeting rooms? 

Were there any recent changes such as updates to mailbox settings, working hours, time zone, or admin modifications? 

In the meantime, please try the following checks: 

Verify your own Outlook working hours and time zone 

Incorrect user time zone or working hours could cause the room to appear available even when it is actually booked.  In fact, misconfigured time zone has been confirmed as a common cause of incorrect room availability. 

Go to Settings (gear icon). 

Select Calendar > View.

Confirm your Working hours and Time zone are correct. 

Check Current Calendar Processing Settings 

Please ask your administrator to verify the current configuration of the affected room by running the following command: 

Get-CalendarProcessing -Identity "your room" | Format-List AutomateProcessing, AllowConflicts, AllowRecurringMeetings, AllRequestInPolicy, AllBookInPolicy

Ensure the following settings are configured correctly: 

AutomateProcessing should be AutoAccept (common default for rooms). 

AllowConflicts should be $false to prevent overlaps. 

AllBookInPolicy or AllRequestInPolicy, ensure they're configured appropriately (such as $true for auto-accept from all if no delegates). 

Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution. 

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Answer 2

If the Exchange Online room resource appears available when scheduling a meeting but shows as "in use" or "not available" after booking, it may be due to several reasons:

1. Incorrect Mailbox Configuration: The resource mailbox may not be configured correctly. You can check the mailbox configuration using the Exchange Management Shell with the following cmdlet:

      get-mailbox <Identity>| fl *type*,*link*,*share*
   

   Ensure that the ResourceType is set to Room and that other attributes are correctly configured.
2. Automate Processing Settings: Confirm that the mailbox is set to respond automatically to meeting invitations. Use the following cmdlet to check the AutomateProcessing attribute:

      Get-CalendarProcessing <Identity> | fl AutomateProcessing
   

   It should be set to AutoAccept. If not, you can change it using:

      Set-MailboxCalendarSettings <Identity> -AutomateProcessing AutoAccept -ConflictPercentageAllowed 0 -maximumConflictInstances 0
   

3. Resource Booking Attendant Logs: You can also investigate the issue by collecting the Resource Booking Attendant logs. This can help identify why the booking is failing. You can download the logs from the Exchange admin center or use PowerShell to export them.

If these steps do not resolve the issue, further investigation may be needed to determine if there are any specific policies or configurations affecting the room resource availability.

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References:

• A resource doesn't respond to meeting requests when using Resource Booking to schedule the resource
• Users see availability but not capacity or description information of resource when scheduling meeting