I just updated my BE server to 20.4, and am trying to get all my servers updated to the latest agents. So far, updating physical boxes has been no problem.
I have two Hyper-V servers (standalone, not clustered), and I have updating the agent on the hosts successfully. I am now trying to update the agent on the guest VMs. After selecting the VMs on which to install the agent, and proceeding through the prompts, the process goes to "Inserting server" and then throws the attached error.
If I click "OK" on the error (once for each VM selected), it takes me back to the install screen, where if I click the install button, the process just repeats. I have tried a single VM at a time with the same result.