Challenge
A Veeam Agent backup job managed by the backup server fails with the following error:
![User-added image]()
Failed to start backup job Error: Unknown invoker method: 2757
Cause
The issue occurs if you have the following software configuration:
- Veeam Agent for Microsoft Windows 3.0.2 is installed on the backed-up computer.
- Veeam Backup & Replication 9.5 U4a or earlier is running on the backup server.
Solution
To resolve the issue, you must upgrade Veeam Backup & Replication to version 9.5 Update 4b. For details about the Veeam Backup & Replication upgrade process, see Release Notes in
this Veeam KB article and the
Upgrading to Veeam Backup & Replication 9.5 Update 4 section in the Veeam Backup & Replication User Guide.