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M365 Backup common errors and actions


The following table will outline common errors that customers will receive in reports for their M365 backup service and the actions a customer can take to resolve them:

Error Solution
Cannot change WebPart ExportMode to ‘All’. WebPart will be skipped To allow the "Export Mode" to be changed by Veeam Backup for Microsoft 365, you must enable the "Allow custom script" option for the affected SharePoint sites.

Failed to find Team mailbox owner account A user with an active Microsoft license needs to be assigned to the team's mailbox to resolve this error.
Mailbox/User does not have a valid M365 license User without a valid M365 license needs to be provided with one to enable them as a mail enabled user.
Inside the portal restore enabled customers are only able to see their own mailbox and not others within the organisation Customers must change scope inside the restore portal to restore objects from the entire organisation.
(Exchange) Failed to access mailbox. The SMTP address has no mailbox associated with it This requires investigation of the backend mailbox and may be because the mailbox has been deleted.
(Exchange) Failed to access mailbox. Access is denied. Check credentials and try again This is potentially an issue with the permissions of the impersonation account.
(Exchange) Failed to find group owner account Orphaned or decommissioned mailbox that is without an owner.
(SharePoint)  Cannot change web part export mode to ‘All’, because custom scripting is disabled for site: <site name>. Web part will be skipped Known issue. Refer to the following to remove/reduce these warnings: Veeam KB4091
(SharePoint)  Item may have a virus reported by the virus scanner plug-in The file appears to be locked by the virus software. Refer to: SharePoint Online or OneDrive for Business Backup Jobs fail with the Warning
(SharePoint)  This site has exceeded its maximum file storage limit. To free up space, delete files you don't need and empty the recycle bin