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BugZero found this defect 564 days ago.
When attempting to add Veeam Backup for Microsoft 365 to Veeam ONE, either of the following error occurs: Failed to connect to “localhost”.404 Not Found
Both errors occur for the same reason, the version of Veeam Backup for Microsoft 365 installed is not supported for integration with Veeam ONE. As documented in the Veeam ONE User Guide > Integration with Veeam Backup for Microsoft 365: Veeam ONE offers monitoring and reporting capabilities for Veeam Backup for Microsoft 365 version 7 and later builds.
Ensure the that Veeam Backup for Microsoft 365 server being added to Veeam ONE is running Veeam Backup for Microsoft 365 7 or higher.