Error: The system cannot find the file specified. Asynchronous read operation failed Failed to upload disk

[klausz]

Case ID: 04656173
-Veeam v.10
A protection group was created and the SQL Always ON cluster was added (physical machines using veeam agent 4.0.1.2169)
A backup job has been created for this protection group.
The bd01 server was successfully backed up
The bd02 server has the error:
Error: The system cannot find the file specified. Asynchronous read operation failed Failed to load the disk. The agent failed to process the {DataTransfer.SyncDisk} method. Server exception: The system cannot find the file specified. Asynchronous read operation failed Unable to retrieve the next transmission command from the block. Number of blocks already processed: [268852]. Failed to download disk '0c25a342-b211-4f97-840e-380f6100c04a'.
I saw in several posts that the problem was the OEM recovery partition that veeam did not have access to and that is why it did not back up, but in my case it does.

[HannesK]

Hello,
I can only recommend to continue with support. It makes no sense to speculate on a forum about the reasons of an error message (especially not, if it is a production cluster).

Logs need to be investigated for a proper answer.

Best regards,
Hannes