1. Connection Forcibly Closed
This error may occur when connecting to SQL Server using TCP/IP.
Error message: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.)
Related cause and solution:
SQL Server Database Engine running on Windows Server 2003 Service Pack 1 and later, Windows may drop connections if the requests arrive faster than SQL Server can service them. This is a security feature of Windows Server 2003 Service Pack 1 and later, which implements a finite queue for incoming TCP connection requests.
How to fix
(1). Edit registry
netsh int tcp show globalshows the offload setting in the OS.
netsh int tcp set global chimney=enabledenables the offload.
2. Transport-level Error When Querying DatabaseErrorMessage:A transport-level error has occurred when receiving results from the server. (provider: TCP Provider, error: 0 - The specified network name is no longer available.)
Related cause and solution:The error is being caused by a timeout exception for long running queries. In previous versions of Visual Studio .NET, the exception was properly represented as a exception with a timeout description.
Set the commandtimeout property of the command object to an appropriate value. Use a value of zero to wait without an exception being thrown.