Unable to restore from deduplicated volume

[max.fontana]

Hi there.
Already opened a case on friday (Case #07407745) but still waiting for the resolution.
Veeam server: physical machine with OS Windows Server 2016. vmware hypervisor with a few Windows server 2022 guest vm. Some have deduplication enabled on volumes. As per KB, I cannot use veeam itself as mount server since its OS version is older than OS of guest vm's.
I have of course another dedicated vm with Windows server 2022 nstalled, deduplication activated and av and firewall disabled which I've used in the past for file recovery.
The issue I'm facing now is that, for some reason this mount server is no longer working so I rebuilt one from scratch but there is no way It can mount the deduped volume...
it fails during the mount process with the error:
[AP] (831016e6) Can't run comand because agent is closed or has error.
Notice that this mount server works flawlessly if I restore file from a non deduped volume.
Any suggestion?
thanks in advance.
max
Italy

[Andreas Neufert]

Did you updated it to latest Windows Patch level?

[max.fontana]

Yes, latest release(august 2024).
I forgot to say that veeam server has dedup service installed and if I specify veeam as mount server, I don't get the same error but just a warning that I must be using the same or later guest OS version. But volumes are being mounted. I'm just unable to restore from the deduped one.