Symptoms

Unable to list all the exchange mailboxes in DS-User and NOC, causing errors as mailboxes get listed, causing DS-NOC to hang or the Tomcat service to crash.

Portal.log errors:
An internal server error occurred. The operation failed., Mailbox '543f669d-56be-4ba2-861f-f346fbb8c7f6' doesn't have a valid license."
'The request failed. The Id property must be set. Mailbox does not exist'.
and 'The account password has expired, as specified by the account settings.'
 

Cause

Mailboxes do not have valid license or the backup account is not licensed.

Workaround

Assign the required license and permissions to the account.