A connection was successfully established with the server, but then an error occurred during the login process. (Error Number: 233)

Question

I am having error while connecting to SQL Server:

Details in Stack Trace are:

===================================  Cannot connect to ServerName.  ===================================  A connection was successfully established with the server, but then an error occurred during the login process. (provider: Shared Memory Provider, error: 0 - No process is on the other end of the pipe.) (.Net SqlClient Data Provider)  ------------------------------ For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&EvtSrc=MSSQLServer&EvtID=233&LinkId=20476  ------------------------------ Server Name: ServerName Error Number: 233 Severity: 20 State: 0   ------------------------------ Program Location:     at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)    at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)    at System.Data.SqlClient.TdsParserStateObject.ReadSniError(TdsParserStateObject stateObj, UInt32 error)    at System.Data.SqlClient.TdsParserStateObject.ReadSni(DbAsyncResult asyncResult, TdsParserStateObject stateObj)    at System.Data.SqlClient.TdsParserStateObject.ReadNetworkPacket()    at System.Data.SqlClient.TdsParserStateObject.ReadBuffer()    at System.Data.SqlClient.TdsParserStateObject.ReadByte()    at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)    at System.Data.SqlClient.SqlInternalConnectionTds.CompleteLogin(Boolean enlistOK)    at System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject, Boolean withFailover)    at System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart)    at System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance)    at System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance)    at System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection)    at System.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection(DbConnection owningConnection, DbConnectionPoolGroup poolGroup)    at System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)    at System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)    at System.Data.SqlClient.SqlConnection.Open()    at Microsoft.SqlServer.Management.SqlStudio.Explorer.ObjectExplorerService.ValidateConnection(UIConnectionInfo ci, IServerType server)    at Microsoft.SqlServer.Management.UI.ConnectionDlg.Connector.ConnectionThreadUser() 

NOTE I have tried

• closing, reopening Sql server Management Studio.

• closing , reopen VS & rebuild Solution

• killed worker process accessing database.

• login credentials are correct.

• able to ping server to make sure its not down.

Answer 1

For SQL2008,

• open Management Studio
• Rt click on instance
• go to properties
• select Security
• Under Server Authentication, check SQL Server and Windows Authentication Mode
• hit OK

Restart the server using configuration manager.

Answer 2

Turn out to be some SQL service was stopped somehow on server. Restarting SQL Server service manually was the solution.