Action Center - Error during installation - The connection was closed by server

Why is the Action Center installer not able to connect to Orchestrator even if the Orchestrator server is reachable from the Action Center machine?

Issue:

When trying to install action center,  not able to get past the section in which user enters the Orchestrator and Identity URLs, receiving an error which states that the connection to Orchestrator could not be established and that the connection was closed by server, as shown in the screen below:

 

 

 

When using Fiddler 4 in order to trace the request, we will see that the tunnel to the Orchestrator server cannot be created, and the error will state: The client and server cannot communicate because they do not possess a common algorithm.

 

Resolution:

Enable TLS1.0 on the machine, until installation finishes.

 

Methods of enabling TLS protocols:

 

  1. Through Registry:
    1. Navigate in the registry to HKLM SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols
    2. Under this segment, you should find the different TLS protocols and their settings, as shown below:
    3. On both Client and Server set the "Enabled" DWORD to 1:]
    4. Restart the machine after altering the registry
  2. Through Powershell
    1. Active TLS protocols can be checked with the following command:
      1. [Net.ServicePointManager]::SecurityProtocol
    2. In order to activate the TLS 1.0 protocol, please use the following command:
      1. [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]::Tls;

 

If enabling the TLS 1.0 protocol through Powershell fails, please check the registry, and enable it from there.

If the registry does not show any TLS protocol keys in the path mentioned above, it means that no TLS protocol is restricted and all of them should be enabled.