Updated April 5, 2017
The following error is displayed in the EOC console when adding an Orion server through Settings > Manage servers:
The client and server cannot communicate, because they do not possess a common algorithm
Any EOC server connecting to any NPM server
TLS 1.0 is required on the NPM server for EOC to connect because EOC uses an earlier version of .NET that does not support TLS 2.0.
Install TLS 1.0 on the Orion servers.