Error Message: An existing connection was forcibly closed by the remote host

Error Message: An existing connection was forcibly closed by the remote host

Action
When making a request to a service connection, the following error message was returned.
Error Message
Error Message: An existing connection was forcibly closed by the remote host
Solution
The error message can be somewhat generic across services, however the commonality is that the service you are connecting to appears to have terminated the connection for some reason.  This can only be analyzed by checking the server-side log and focus on the server-side to determine what is the issue.

Salesforce Example:
Salesforce has a resource governor which may terminate connection. 

The error message states the connection was forcefully closed by the remote host. This is a good indicator the resource governor has abruptly terminated the connection because the limit has been reached.

 If the limit has been reached, you would need to contact Salesforce for assistance to lift the limit.