Veeam Backup Enterprise Manager fails to collect data from a Veeam Backup server with the following error:
Return argument has an invalid type.
The following error can be seen in VeeamBES.log:
[timestamp] Info Reporting data were successfully collected from the server [server.local]
[timestamp] Error Interrupting collect session. Return argument has an invalid type.
[timestamp] Error Unable to collect data from Veeam Backup Server xxx.xxx.xx.x
[timestamp] Error System.InvalidCastException: Return argument has an invalid type.
The version of Veeam Backup Enterprise Manager differs from the version of Veeam Backup & Replication.
Make sure that Veeam Backup Enterprise Manager and Veeam Backup server have the same version. Veeam Backup Enterprise Manager can only collect data from backup servers of the same version.