Problem Description
Mailbox backups fail with an error indicating that the Shared/Resource Mailbox license limit has been reached. This prevents successful backup of mailboxes categorized as Shared or Resource mailboxes.
Cause
The issue occurs when all allocated Shared/Resource Mailbox licenses are fully utilized.
Shared Mailbox licenses are typically assigned as a percentage of active user licenses (e.g., 50%).
Product Limitation: Administrators cannot manually add or edit Shared Mailbox licenses at this time.
Error/Traceback:
Error message:
ESMBLICENSELIMITREACHEDLicense utilization details:
Active Licenses: Within limit
Shared/Resource Licenses: Fully utilized (e.g., 80/80)
Resolution
To resolve the issue, increase the number of active user licenses. This automatically increases the Shared Mailbox license count based on the allocation ratio.
Steps to Increase the Active Licenses
Log in to the MSC console with admin credentials.
Navigate to the customer and modify the License.
Allocate additional active user licenses and save the changes.
📝Note
Direct management of Shared Mailbox licenses is not currently available for MSP