Onboarded server on VeeamOne appears greyed out and shows error "Uncaught exception thrown by method called Reflection""

The server appears like this 192.168.10.20 (Not Available) and its greyed out but the VMs on the server is not greyed out

Hi @Danyang007 -

Where exactly is this error? Can you provide a screenshot?

Thank you.

This is the Veeamone Server.

Hi @Danyang007 

Have you had a look at the requirements here: https://helpcenter.veeam.com/docs/one/deployment/ports.html?ver=120

Looks like your Veeam One install is not able to connect to your VMware infrastructure correctly. 

Hello @dips 

The server is a hyper V server and the Windows firewall is already turned off. I dont think the port should still affect it, but will check.

Also it worth nothing that the servers were added successfully 3 days ago and all was fine up until this morning when this just suddenly came up.

No worries @Danyang007 

On the top left corner, you have a link where it says ‘Configuration issues (3 detected)’ 

Have you had a look there?

@dips Yes i have checked it. there is no info there, just says connection failure to 10.4.0.XX .

I removed a server that was having the same issue and tried to add it again, it still comes up with the same error “ Uncaught exception thrown by method called Reflection ”.

Do not even know what that error is pointing to

It may be worth opening a Support Case as well if you have not yet done so. 

Hi @Danyang007 -

Have you tried adding the host via hostname iinstead of IP? I saw a similar issue on the Forums.

Have you performed any Veeam upgrades?

Also, is UAC on, on this Hyper-V host? Have you recently installed Win updates? Have you tried something as simple as rebooted both the HV and VONE servers, then re-attempting to add?

Nice to hear you got it working!

Welcome, glad you got it working! :) 

Interesting that you had to run a reinstall again, but nice to see it working.

Makes me wonder if the Veeam ONE agent wasn’t running properly and reinstalling resolved that issue?