Change the main.cbl program to display the loginform first and then start the application with the main form depending on the results of the login.

Example:

main.cbl

       class-id winformlogin.Main.
       method-id Main static
           attribute System.STAThread.
       local-storage section.
       01 mainForm type winformlogin.Form1.
       01 loginForm type winformlogin.LoginForm1.
       01 myresult  type DialogResult.
       procedure division.
       
           set loginForm to new winformlogin.LoginForm1
           set myresult to loginForm::ShowDialog
           if myresult = type DialogResult::OK
              set mainForm to new winformlogin.Form1()
              invoke type System.Windows.Forms.Application::EnableVisualStyles()
              invoke type System.Windows.Forms.Application::Run(mainForm)
           else
              invoke type System.Windows.Forms.Application::Exit
           end-if
           goback.
       
       end method.
       end class.

LoginForm1.cbl

       class-id winformlogin.LoginForm1 is partial
                 inherits type System.Windows.Forms.Form.

       working-storage section.
 
       method-id NEW.
       procedure division.
           invoke self::InitializeComponent()
           goback.
       end method.

       method-id btnOK_Click final private.
       procedure division using by value sender as object 
                                         e as type System.EventArgs.
           set self::DialogResult to type DialogResult::OK
           invoke self::Close()
           goback.
       end method.

       method-id btnCancel_Click final private.
       procedure division using by value sender as object
                                         e as type System.EventArgs.
           set self::DialogResult to type DialogResult::Cancel
           invoke self::Close()
           goback.
       end method.

       end class.

Thanks Chris. Perfect! Thank you very much

Thanks Chris. Perfect! Thank you very much

Thanks Chris. Perfect! Thank you very much