Question: We have an automation test running on IE using WatiN. This test requires handling the logon dialog.
How I should process it by Watin?

Answer: 
In Windows 7, the Logon handler became a WPF component and no longer a part of the IE. I think this even applies to IE8 or higher already.

Below is the code we use for handeling these dialogs. It's something I wrote myself, so feel free to use it, as long as credit is given where due.

```
using System.Windows.Automation;
using System.Linq;
using WatiN.Core.DialogHandlers;
using WatiN.Core.Native.Windows;

namespace DialogHandlers
{
    public class Windows7LogonDialogHandler : LogonDialogHandler
    {
        #region Private Fields

        private readonly string _mUsername;
        private readonly string _mPassword;
        private readonly AndCondition _mListCondition = new AndCondition(new PropertyCondition(AutomationElement.IsEnabledProperty, true), new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.ListItem));
        private readonly AndCondition _mEditCondition = new AndCondition(new PropertyCondition(AutomationElement.IsEnabledProperty, true), new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.Edit));
        private readonly AndCondition _mButtonConditions = new AndCondition(new PropertyCondition(AutomationElement.IsEnabledProperty, true), new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.Button));

        #endregion

        #region Constructor

        public Windows7LogonDialogHandler(string username, string password)
            : base(username, password)
        {
            _mUsername = username;
            _mPassword = password;
        }

        #endregion

        #region Public Members

        public override bool HandleDialog(Window window)
        {
            if (CanHandleDialog(window))
            {
                var win = AutomationElement.FromHandle(window.Hwnd);
                var lists = win.FindAll(TreeScope.Children, _mListCondition);
                var buttons = win.FindAll(TreeScope.Children, _mButtonConditions);
                var another = (from AutomationElement list in lists
                               where list.Current.ClassName == "UserTile"
                               where list.Current.Name == "Use another account"
                               select list).First();
                another.SetFocus();

                foreach (var edit in from AutomationElement list in lists
                                     where list.Current.ClassName == "UserTile"
                                     select list.FindAll(TreeScope.Children, _mEditCondition)
                                         into edits
                                         from AutomationElement edit in edits
                                         select edit)
                {
                    if (edit.Current.Name.Contains("User name"))
                    {
                        edit.SetFocus();
                        var usernamePattern = edit.GetCurrentPattern(ValuePattern.Pattern) as ValuePattern;
                        if (usernamePattern != null) usernamePattern.SetValue(_mUsername);
                    }
                    if (edit.Current.Name.Contains("Password"))
                    {
                        edit.SetFocus();
                        var passwordPattern = edit.GetCurrentPattern(ValuePattern.Pattern) as ValuePattern;
                        if (passwordPattern != null) passwordPattern.SetValue(_mPassword);
                    }
                }
                foreach (var submitPattern in from AutomationElement button in buttons
                                              where button.Current.AutomationId == "SubmitButton"
                                              select button.GetCurrentPattern(InvokePattern.Pattern) as InvokePattern)
                {
                    submitPattern.Invoke();
                    break;
                }
                return true;
            }
            return false;
        }

        public override bool CanHandleDialog(Window window)
        {
            return window.ClassName == "#32770";
        }

        #endregion
    }
}

```
You can try this

```
Browser browser = new IE();
WatiN.Core.DialogHandlers.LogonDialogHandler ldh = 
        new WatiN.Core.DialogHandlers.LogonDialogHandler("UserName","Password");
browser.DialogWatcher.Add(ldh);
browser.ShowWindow(NativeMethods.WindowShowStyle.Maximize);
browser.GoTo("http://www.yoururl.com");

```

However, if you are using Windows 7 you will probably need to [look deeper](https://stackoverflow.com/questions/2841120/watin-logondialoghandlers-not-working-correctly-in-windows-7)