public void AutoOpen() { ExcelIntegration.RegisterUnhandledExceptionHandler(ex => "!!! EXCEPTION: " + ex.ToString()); ComServer.DllRegisterServer(); try { _comAddin = new qXLComAddIn(); ExcelComAddInHelper.LoadComAddIn(_comAddin); } catch (Exception ex) { MessageBox.Show(@"Error loading COM AddIn: " + ex); } }