O365 Mailboxes after 11.36 upgrade

Hi ​@atitagain 

Good day!

The error you're encountering is 'Throttling from Exchange. Failed to process mailbox due to [Value cannot be null. Parameter name: key]', is likely related to throttling issues that are common in Exchange Online backups.

Please verify the configuration
Streams per access node: 10; if we have 2 Access nodes, set it to 20 Streams
Azure Apps: 5

Please try running the failing Mailbox separately and see how it goes

Please work with Office365 Admin to relax the throttling on the Tenant Level. refer the below kb articlehttps://kb.commvault.com/article/68619

 If the issue persists, consider reaching out to Commvault support for further assistance

low & behold the next evenings O365 backup’s ran 100% ……….. no changes needed. 

​@Syed_S thanks for the info. 

​@atitagain It will come and go until you complete what ​@Syed_S stated above.