Question

I’ve created a Winform that connects to SQL Server Express x64 using Trusted Connection string.

On the development machine (Which SQL Server is running on as well) the Winform works 100%, the resulting connection string is:

Persist Security Info=False;
Integrated Security=true;
Initial Catalog=BushBreaksLodgeManager;
server=.\SQLEXPRESS

As soon as I try the same win form on a networked PC it fails to connect. On the remote machine I can see the development machine via Network places i.e. \\JOHN-WIN7PC

The remote PC’s resulting connection string is:

Persist Security Info=False;
Integrated Security=true;
Initial Catalog=BushBreaksLodgeManager;
server=\\JOHN-WIN7PC\SQLEXPRESS

I have also enabled TCP-IP on SQL Server (It was set to <default>), turned off all firewalls, anti-malware (not that this should interfer) and anti-virus is not installed on either machine.

SQL database settings are as follows:
==================================================
Authentication method: Windows Authentication
Database: BushBreaksLodgeManager
ServerName: JOHN-WIN7PC\SQLEXPRESS
Instancename: SQLEXPRESS
Computername: JOHN-WIN7PC

Sql Server settings
==================================================
Mixed mode (Win auth and Sql Server)
Connections -> Allow remote connections = true

Any help in this regard would be appreciated as I am at a loss.

I have pasted the exception below:

2011/11/18 04:55:50 PM : Process: UtilsDatabase -> TestDatabaseConnection
2011/11/18 04:56:05 PM : Process: UtilsDatabase -> TestDatabaseConnection Connection failed
2011/11/18 04:56:05 PM : Settings value -> UseIntergratedSecurity: False
2011/11/18 04:56:05 PM : Settings value -> Server: \\JOHN-WIN7PC\SQLEXPRESS
2011/11/18 04:56:05 PM : Settings value -> Database name: BushBreaksLodgeManager
2011/11/18 04:56:05 PM : Connection String: Persist Security Info=False;Integrated Security=true;Initial Catalog=BushBreaksLodgeManager;server=\\JOHN-WIN7PC\SQLEXPRESS

==================== New Exception ====================
2011/11/18 04:56:05 PM

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 25 - Connection string is not valid)

.Net SqlClient Data Provider

   at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning()
   at System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity)
   at System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, TimeoutTimer timeout, SqlConnection owningObject)
   at System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(ServerInfo serverInfo, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, TimeoutTimer timeout)
   at System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, TimeoutTimer timeout, 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.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options)
   at System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject)
   at System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject)
   at System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject)
   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 BushBreaksLodgeManager.UtilsDatabase.TestDatabaseConnection()

Void OnError(System.Data.SqlClient.SqlException, Boolean)

Answer 1

I think the error is very simple. When connecting to SQL Server you don’t prefix the server name with \\, So instead of server=\\JOHN-WIN7PC\SQLEXPRESS you should use server=JOHN-WIN7PC\SQLEXPRESS.