title: ODAC & C# - TNS: Connect timeout occurred - Connecting only through VS2005 debugger
body: <p>I am new to Oracle, and there is an issue I am facing. When I run the application from IDE - Visual Studio 2005, The database connection is established smoothly, but when I run an installed version of the app, the DB connection fails and I get a TNS: Connect timeout occurred error.</p>
  
  <p>I tried with SQLNET.ORA and similar solutions found online, but I could not resolve the issue. I wonder why this happens, since the application running through the IDE and through an installation is on the same PC. I made sure the TNSNAMES.ORA file was correctly edited, and I can connect through an instance of the application running directly on Visual Studio.</p>
  
  <pre><code>public bool connectToDatabase(string dbConnStr)
  {
      try
      {
          databaseConnection = dbConnStr;
          OracleConnection dbConn = new OracleConnection(databaseConnection);
          if (dbConn == null)
          {
              CreateDLLLogFiles.ErrorLog(CreateDLLLogFiles.FileName, "Connection object is null");
              return false;
          }
          if (dbConn.State.ToString().Equals("Closed", StringComparison.OrdinalIgnoreCase))
          {
              CreateDLLLogFiles.ErrorLog(CreateDLLLogFiles.FileName, "DB connection - " + dbConn.ConnectionString);
              dbConn.Open();
              return true;
          }
      }
      catch (Exception ex)
      {
          CreateDLLLogFiles.ErrorLog(CreateDLLLogFiles.FileName, ex.Message + "\n" + ex.StackTrace);
          CreateDLLLogFiles.ErrorLog(CreateDLLLogFiles.FileName, "DB String - " + databaseConnection);
  
          return false;
      }
      return false;
  }
  </code></pre>
  
  <p>The stack trace reads like this:</p>
  
  <pre><code>7/22/2010 6:38:51 PM    ORA-12170: TNS:Connect timeout occurred
     at Oracle.DataAccess.Client.OracleException.HandleErrorHelper(Int32 errCode, OracleConnection conn, IntPtr opsErrCtx, OpoSqlValCtx* pOpoSqlValCtx, Object src, String procedure, Boolean bCheck)
     at Oracle.DataAccess.Client.OracleException.HandleError(Int32 errCode, OracleConnection conn, IntPtr opsErrCtx, Object src)
     at Oracle.DataAccess.Client.OracleConnection.Open()
     at SQL.connectToDatabase(String dbConnStr)
  </code></pre>
  
  <p>The tnsnames.ora is something like this:</p>
  
  <pre><code>MySource =
    (DESCRIPTION =
      (CONNECT_TIMEOUT=180)(RETRY_COUNT=2)
      (ADDRESS_LIST =
          (ADDRESS = (PROTOCOL = TCP)(HOST = 125.63.77.232)(PORT = 1521)))
      (CONNECT_DATA =
        (SERVER = DEDICATED)
        (SERVICE_NAME = MySource )
      )
    )
  </code></pre>
  
  <p>In the meanwhile, I was being issued a ContextSwitchDeadlock error through the debugger, so I followed instructions and changed the attribute from STAThread to MTAThread on Main(). No more ContextSwitchDeadlock - and Still, the connection issue persists. </p>
  
  <p>I was hoping you could shed some light on the issue - I am close to pulling my hair out. Any insight would be appreciated.</p>