I have a C # application that connects to a named instance of SQL Express on a local machine using OleDBConnection:
_connection = new OleDbConnection(_strConn);
_connection.Open();
_strConn is something like this: "Provider=sqloledb;Data Source=.\NAMEDINSTANCE;Initial Catalog=dbname;User Id=sa;Password=password;"
If I debug the application, the connection works fine. If I run the application from Windows Explorer (the same debug compilation), I get "OleDBException: Login timed out" in the Open () line after 30 seconds. The strange thing is the exception, even if I attach the debugger to exe. I see that the connection string is correct and everything seems fine. I cannot process additional information in the SQL Express or SQL Activity Monitor error log.
If that helps, here's what:
System.Data.OleDb.OleDbException: Login timeout expired
at System.Data.OleDb.OleDbConnectionInternal..ctor(OleDbConnectionString constr, OleDbConnection connection)
at System.Data.OleDb.OleDbConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningObject)
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.OleDb.OleDbConnection.Open()
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