Transport level error - An existing connection was forcibly closed by the remote host

This issue is related to your network / SQL Server / .NET.

The situation occurs when the connection between SQL Server and TM Master v2 has been closed.

The error message will be displayed if a connection is drawn from the connection pool and the connection to the server has been lost.

There is no way for a connection in the pool to know that the connection has been severed.

If the problem persists, please contact your IT department regarding the server and/or network.

You could suggest that they take a look at this article which explains possible causes for this error:

http://blogs.msdn.com/b/spike/archive/2009/04/16/a-transport-level-error-has-occurred-when-sending-the-request-to-the-server-provider-tcp-provider-error-0-an-existing-connection-was-forcibly-closed-by-the-remote-host.aspx

And this article, which explains the need for installing "Reliability Update 1 for the .NET Framework 4":

http://blogs.msdn.com/b/adonet/archive/2011/11/05/minimizing-connection-pool-errors-in-sql-azure.aspx

Download page for Microsoft .NET Framework 4 Reliability Update 1 (KB2533523)

http://www.microsoft.com/en-us/download/details.aspx?id=27014