Issue:

• Connection unexpectedly ends while attempting a send

Environment:

• Windows 2012 R2 version 3.0

Additional Information:

Error text:
"An error occurred during an attempt to read the federation metadata. Verify that the specificed URL or host name is a valid federation metadata endpoint.

Verify your proxy server setting. For more information about how to verify your proxy server setting, see the AD FS Troubleshooting Guide (http://go.microsoft.com/fwlink/?LinkId=182180).

Error message: The underlying connection was close: An unexpected error occurred on a send."

Cause:

Your Windows 2012 environment is running older TLS versions doesn't support TLS 1.2

Resolution:

1. Enable TLS 1.2