Hi what do you mean by WD? My mind keeps thinking WD = Western Digital so some kind of NAS?

Its most likely if a server is showing unavailable you’ve either got a hosts file edit that’s been lost or some other type of network config or firewall rule that’s changed.

Its also possible that upgrading has changed your supported TLS ciphers to prevent communication as they’re no longer compatible.

Please provide more details

Hi ​@dannodeg, I would also recommend taking a look at the network (dns) properties to see if you have the right parameters there. BTW, could you please answer the question from Paul above. This is critical in pinpointing and resolving your issues. I did an upgrade as well without issues as shared here. What are the steps you employed during the upgrade? We will be happy if you could share a screenshot of the error msg with us.

It was just a straight up in place upgrade to Windows Server 2025.

I added one of the devices to the hosts file and was then able to ping using host name but after a rescan the device was still showing unavailable.

What version of Veeam are you using?  Did you check the logs here C:\ProgramData\Veeam\Backup

In addition to the comment from ​@Chris.Childerhose. Here is a similar issue I resolved in this blog post. https://techdirectarchive.com/2024/11/07/fix-missing-path-and-delete-a-veeam-backup-repository/. Let me know if this helps

Hi ​@dannodeg this will be because of SMB changes in WS 2025. Try connecting to the share directly from the same server that is being the gateway to these SMBs, guessing it’s this one. It could be they’re old NAS devices using SMB 1.0, or another auth change.

Perfect colocation Michael! 
​@dannodeg, here you can see a brief of new things about SMB on WS 2025:
What's new in Windows Server 2025 | Microsoft Learn

It was just a straight up in place upgrade to Windows Server 2025.

I added one of the devices to the hosts file and was then able to ping using host name but after a rescan the device was still showing unavailable.

 

 

And this is one of the reasons why I never do in-place upgrades for Veeam. Best practice is to create a new Windows server, export the Veeam configuration backup file, and import it into the new Windows server, choosing the migrate option as described here. 

Regarding your issue, I noticed that the gateway is set to auto. This means Veeam will use any available windows server to access the SMB share, not necessarily the Veeam server itself. Click on “Microsoft Windows” in the Backup Infrastructure view you’re showing above. Check each of the servers in the list, and make sure it can contact the SMB share from each of the servers listed there. If only some can, or there are some in the list you don’t want to be acting as a gateway, edit the properties of the repository and choose a specific gateway server.

​@dannodeg  - I wanted to follow up and see if you were able to get this issue resolved so we can mark an answer even if it is your details.  Let us know.