About the SQLServer2008 problem solution:
problem: In relation to a network-related or instance-specific error occurred while SQL Server was establishing a connection. The server was not found or could not be accessed. Verify that the instance name is correct, and that SQL Server is configured to allow remote connections. (provider: named pipe provider , error:40- Unable to open a connection to SQL Server ) (Microsoft SQL Server, Error : 2)
Such as:
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Unable to connect to . .
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in with a network-related or instance-specific error occurred while SQL Server was establishing a connection. The server was not found or could not be accessed. Verify that the instance name is correct, and that SQL Server is configured to allow remote connections. (provider: named pipe provider , error:40- Unable to open a connection to SQL Server ) (. Net SqlClient Data Provider)
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for help information, click : Http://go.microsoft.com/fwlink? prodname=microsoft+sql+server&evtsrc=mssqlserver&evtid=2&linkid=20476
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Error number : 2
severity : 20
status : 0
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Program Location :
in System.Data.SqlClient.SqlInternalConnection.OnError (SqlException exception, Boolean breakconnection)
in System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning (Tdsparserstateobject stateobj)
in System.Data.SqlClient.TdsParser.Connect (ServerInfo serverinfo, Sqlinternalconnectiontds Connhandler, Boolean ignoresniopentimeout, Int64 Timerexpire, Boolean encrypt, Boolean Trustservercert, Boolean integratedsecurity, SqlConnection Owningobject, Boolean withfailover)
in System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin (ServerInfo serverinfo, String NewPassword, Boolean ignoresniopentimeout, Int64 timerexpire, SqlConnection owningobject, Boolean withfailover)
in System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover (string host, String newpassword, Boolean Redirecteduserinstance, SqlConnection owningobject, sqlConnectionString connectionoptions, Int64 Timerstart)
in System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist (SqlConnection owningobject, sqlConnectionString connectionoptions, String newpassword, Boolean redirecteduserinstance)
in System.Data.SqlClient.SqlInternalConnectionTds. ctor (dbconnectionpoolidentity identity, sqlConnectionString connectionoptions, Object providerinfo, String NewPassword, SqlConnection owningobject, Boolean redirecteduserinstance)
in System.Data.SqlClient.SqlConnectionFactory.CreateConnection (dbconnectionoptions options, Object Poolgroupproviderinfo, Dbconnectionpool Pool, DbConnection owningconnection)
in System.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection (DbConnection owningconnection, Dbconnectionpoolgroup Poolgroup)
in System.Data.ProviderBase.DbConnectionFactory.GetConnection (DbConnection owningconnection)
in System.Data.ProviderBase.DbConnectionClosed.OpenConnection (DbConnection outerconnection, Dbconnectionfactory connectionfactory)
in System.Data.SqlClient.SqlConnection.Open ()
in Microsoft.SqlServer.Management.UI.VSIntegration.ObjectExplorer.ObjectExplorer.ValidateConnection ( Uiconnectioninfo ci, iservertype server)
in Microsoft.SqlServer.Management.UI.ConnectionDlg.Connector.ConnectionThreadUser ()
for this question, the literal meaning, is missing the instance, because in the installation, the choice is the default instance, when logged in here, because is the local login, directly use the local. Select windows authentication and the result is an error. Then, when the service is viewed, the service for the default instance is not found. So the first step is to reinstall the SqlServer2008, using a new instance of your own name. After the installation is complete, review the service and discover that the name of the new instance is already in service.
Right-click the properties of the new service, and in the login, select the login identity is the local system account. Then log in, at the login interface, server type Select Database engine, service name Select Browse More, under the database engine select the native database engine, that is, the new instance corresponding to the engine. Log in directly with Windows identity.
An instance problem solution was not found on the SQLServer2008 link