Unable to add vCenter 6.5 to virtual machine manager 2016 RRS feed

  • Question

  • Hello,

    I am having an issue where i can't add vCenter 6.5 to virtual machine manager 2016.  I keep getting the following error.

    Sunday, April 29, 2018 3:48 PM

All replies

  • I figured it out.  I had my servers hardened a little to much.  I disable a few week ciphers and TLS 1.0 during the build process.  I re enabled them and some what got it to connect.  But now i am getting this error when it trys to add the vcenter.  Any help would be greatly appreciated. My vCenter is a virtual application with no firewall or virus protection.  I have checked the services and they are all running.  My VMM server also has no firewall.  I have restarted my vCenter a few times.

    Sunday, April 29, 2018 11:52 PM
  • For some reason when it is connecting to the vCenter if is failing during the Install virtual switch extension.

    Monday, April 30, 2018 10:55 PM
  • For anyone stumbling on this, I had a similar issue with SCVMM 2016 (Update rollup 8) and vCenter 6.7.

    My issue was needing to go into the management interface of my vCenter (fqdn.domain.local:5480), going to Firewall, and adding an entry to explicitly allow access from the subnet where my SCVMM server was.

    My SCVMM server was for example IP with a subnet mask of

    In the Firewall rule, select the right NIC, type IP address of (to include the whole subnet) and give the Subnet Prefix Length of 24. If your subnet mask is not, you gotta figure out your SPL from your networking team.

    Action should be Accept.

    When I did this, and ensured that the appropriate account I was using to connect to vCenter had appropriate SSH rights (in this same management interface, go to the Access section), I was finally able to add my vCenter server. I can also verify that I've been able to add my ESXi hosts and cluster.

    Tuesday, April 14, 2020 11:49 PM