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UIAutomation throws AccessViolationException on Windows 11

The issue:
We have an application written in C# that uses UIAutomation to get the current text (either selected or the word behind the carret) in other applications (Word, OpenOffice, Notepad, etc.).
All is working great on Windows 10, even up to 21H2, last update check done today.
But we had several clients informing us that the application is closing abruptly on Windows 11.
After some debugging I've seen some System.AccessViolationException thrown when trying to use the TextPatternRange.GetText() method:
System.AccessViolationException: 'Attempted to read or write protected memory. This is often an indication that other memory is corrupt.'
What we've tried so far:
Setting uiaccess=true in manifest and signing the app : as mentionned here https://social.msdn.microsoft.com/Forums/windowsdesktop/en-US/350ceab8-436b-4ef1-8512-3fee4b470c0a/problem-with-manifest-and-uiaccess-set-to-true?forum=windowsgeneraldevelopmentissues => no changes (app is in C:\Program Files\
In addition to the above, I did try to set the level to "requireAdministrator" in the manifest, no changes either
As I've seen that it may come from a bug in Windows 11 (https://forum.emclient.com/t/emclient-9-0-1317-0-up-to-9-0-1361-0-password-correction-crashes-the-app/79904), I tried to install the 22H2 Preview release, still no changes.
Reproductible example
In order to be able to isolate the issue (and check it was not something else in our app that was causing the exception) I quickly made the following test (based on : How to get selected text of currently focused window? validated answer)
private void btnRefresh_Click(object sender, RoutedEventArgs e)
{
var p = Process.GetProcessesByName("notepad").FirstOrDefault();
var root = AutomationElement.FromHandle(p.MainWindowHandle);
var documentControl = new
PropertyCondition(AutomationElement.ControlTypeProperty,
ControlType.Document);
var textPatternAvailable = new PropertyCondition(AutomationElement.IsTextPatternAvailableProperty, true);
var findControl = new AndCondition(documentControl, textPatternAvailable);
var targetDocument = root.FindFirst(TreeScope.Descendants, findControl);
var textPattern = targetDocument.GetCurrentPattern(TextPattern.Pattern) as TextPattern;
string text = "";
foreach (var selection in textPattern.GetSelection())
{
text += selection.GetText(255);
Console.WriteLine($"Selection: \"{selection.GetText(255)}\"");
}
lblFocusedProcess.Content = p.ProcessName;
lblSelectedText.Content = text;
}
When pressing a button, this method is called and the results displayed in labels.
The method uses UIAutomation to get the notepad process and extract the selected text.
This works well in Windows 10 with latest update, crashes immediately on Windows 11 with the AccessViolationException.
On Windows 10 it works even without the uiaccess=true setting in the manifest.
Questions/Next steps
Do anyone know/has a clue about what can cause this?
Is Windows 11 way more regarding towards UIAutomation?
On my side I'll probably open an issue by Microsoft.
And one track we might follow is getting an EV and sign the app itself and the installer as it'll also enhance the installation process, removing the big red warnings. But as this is an app distributed for free we had not done it as it was working without it.
I'll also continue testing with the reproductible code and update this question should anything new appear.

I posted the same question on MSDN forums and got this answer:
https://learn.microsoft.com/en-us/answers/questions/915789/uiautomation-throws-accessviolationexception-on-wi.html
Using IUIautomation instead of System.Windows.Automation works on Windows 11.
So I'm marking this as solved but if anyone has another idea or knows what happens you're welcome to comment!

C# IE11 Automation - Cannot Connect To Open IE Window

I'm trying to connect to an Internet Explorer window that is already open. Once connected I need to send some keystrokes (via SendKeys) to the IE window for some processing. I've got the following code below that works up until the SendKeys command. It finds the IE window titled "Graphics Database". When it hits "SendKeys.Send("{TAB}");" I get the error "An unhandled exception of type 'System.NullReferenceException' occurred".
Additional information: I also get the following on the NullReferenceException error. The weird thing is if I code to open a new IE window and then use SendKeys it works fine. Connecting to an existing windows seems to cause this issue.
SendKeys cannot run inside this application because the application is not handling Windows messages. Either change the application to handle messages, or use the SendKeys.SendWait method.
Can anyone please help me figure out what to do to fix this?
Andy
InternetExplorer IE = null;
// Get all browser objects
ShellWindows allBrowsers = new ShellWindows();
if (allBrowsers.Count == 0)
{
throw new Exception("Cannot find IE");
}
// Attach to IE program process
foreach (InternetExplorer browser in allBrowsers)
{
if (browser.LocationName == "Graphics Database")
{
MessageBox.Show ("Found IE browser '" + browser.LocationName + "'");
IE = (InternetExplorer)browser;
}
}
IE.Visible = true;
System.Threading.Thread.Sleep(2000);
SendKeys.Send("{TAB}");
SendKeys.Send("G1007");
SendKeys.Send("{ENTER}");

I was able to resolve this issue. I could never get the IE.Visible = true to work. This seemed to do nothing in my code. I had to use the SetForegroundWindow() to set the focus to the IE window.
// Find the IE window
int hWnd = FindWindow(null, "Graphics Database - Internet Explorer");
if (hWnd > 0) // The IE window was found.
{
// Bring the IE window to the front.
SetForegroundWindow(hWnd);
This site helped me immensely with getting the SetForegroundWindow() working.
http://forums.codeguru.com/showthread.php?460402-C-General-How-do-I-activate-an-external-Window

Andy please bear with me as this will be long. First you are going to want to look mshtml documentation and Dom. https://msdn.microsoft.com/en-us/library/aa741314(v=vs.85).aspx I don't know why automation is so convoluted but it is. The UIautomation class works great for windows apps but has nothing really for IE that I've been able to find. Others will point to third parties like waitn and selenium. Waitn appears to no longer be supported and selenium won't let you grab an open IE browser. I have gone down this path recently because I wanted to be able to create an app to store my web passwords and auto fill them in since I can't save my username and passwords in browser due to security restrictions. I have an example here and hope it helps. First open up IE and navigate to http://aavtrain.com/index.asp. Then have a console project with mshtml referenced and shdocvw. Here is code below. It gets the window then finds elements for username, password, and submit. then populates the username and password and clicks the submit button. I don't have a login to this site so it won't log you in. I have been using it for my testing. Problem I have is sites with javascript login forms. If you get further with this info please post back as I am still trying to evolve the concepts and create something reusable.
SHDocVw.ShellWindows shellWindows = new SHDocVw.ShellWindows();
Console.WriteLine("Starting Search\n\n\n");
foreach (SHDocVw.InternetExplorer ie in shellWindows)
{
if (ie.LocationURL.Contains("aavtrain"))
{
Console.WriteLine(ie.LocationURL);
Console.WriteLine("\n\n\n\n");
Console.WriteLine("FOUND!\n");
mshtml.HTMLDocument document = ie.Document;
mshtml.IHTMLElementCollection elCol = document.getElementsByName("user_name");
mshtml.IHTMLElementCollection elCol2 = document.getElementsByName("password");
mshtml.IHTMLElementCollection elCol3 = document.getElementsByName("Submit");
Console.WriteLine("AutofillPassword");
foreach (mshtml.IHTMLInputElement i in elCol)
{
i.defaultValue = "John";
}
foreach (mshtml.IHTMLInputElement i in elCol2)
{
i.defaultValue = "Password";
}
Console.WriteLine("Will Click Button in 2 seconds");
Thread.Sleep(2000);
foreach (mshtml.HTMLInputButtonElement i in elCol3)
{
i.click();
}
}
}
Console.WriteLine("Finished");

C# .NET 4.5 Getting target of shortcut without shell32.shell()

I'm not a very experienced programmer and new at C#, and I'm having some problems getting the target of a shortcut using shell32.shell().
I found the code here on stackoverflow - and it works beautifully on regular Windows PC's, but when executed on a Citrix virtualized Windows desktop (where I need it to run) it breaks.
The code runs through shortcuts in a folder via a foreach loop, and filters out any that has an executable target. Problem is that to find the target of the shortcut I use the code below, and as soon as it is called the foreach breaks and doesn't progress any further (on Citrix).
I have determined that the break happens at the line "var shl = new Shell32.Shell();", the code after that line doesn't fire and it exits the foreach (but continues executing code after the foreach).
public static string GetLnkTarget(string lnkPath)
{
var shl = new Shell32.Shell();
lnkPath = System.IO.Path.GetFullPath(lnkPath);
var dir = shl.NameSpace(System.IO.Path.GetDirectoryName(lnkPath));
var itm = dir.Items().Item(System.IO.Path.GetFileName(lnkPath));
var lnk = (Shell32.ShellLinkObject)itm.GetLink;
return lnk.Target.Path;
}
Does anyone know of an alternate way to find the target of a shortcut that'll work in a Citrix virtualized environment?

I don't know what caused the issue with Shell32.Shell() specifically in the Citrix environment, but I found another way that works for me.
The answer was provided by user djdanlib here: https://stackoverflow.com/a/8661371/5992820
"Add IWshRuntimeLibrary as a reference to your project. Add Reference, COM tab, Windows Scripting Host Object Model.
Here is how I get the properties of a shortcut:
IWshRuntimeLibrary.IWshShell wsh = new IWshRuntimeLibrary.WshShellClass();
IWshRuntimeLibrary.IWshShortcut sc = (IWshRuntimeLibrary.IWshShortcut)wsh.CreateShortcut(filename);
The shortcut object "sc" has a TargetPath property."

Calling C# BHO methods from Javascript In Internet Explorer 10 (Release preview)

I'm trying to develop a BHO for the release preview of IE 10. The BHO needs to be able to allow javascript to call a C# function.
I've followed the instructions available here:
Calling C# BHO methods from Javascript
These instructions work great in IE 9.
Unfortunately, I've found that they only work for the first tab created in IE 10. The second and subsequent tabs do not expose the BHO interface to Javascript. On occasion, new tabs work, but most of the time they do not. Moreover, it fails silently. I'm guessing this has something to do with the process model -- but again, it works fine in IE 9 (which has the same process model).
Here is the specific snippet of code that I'm using:
private void InstallJSObject(IHTMLWindow2 window)
{
// Install our javascript object
IExpando windowEx = (IExpando)window;
PropertyInfo property = windowEx.GetProperty("myBHO", System.Reflection.BindingFlags.IgnoreCase);
if (property == null)
{
property = windowEx.AddProperty("myBHO");
}
property.SetValue(windowEx, this, null);
}
Before posting, I researched the following: http://bit.ly/R9qldf

var myATL = new ActiveXObject("MySampleATL.MyClass");
if (myATL.IsBHOInstalled)
alert (myATL. SayHelloFromBHO());
else
alert ("BHO isn't installed now !");
window.external.AddFavorite(<url>, "text");
Extracted from here.
The the blog is dated back to April'07, still, may be this is what you were looking for..

How to obtain DefragAnalysis using C#

I am currently developing an application in C# (.NET 4.0) that should have as a part of its functionality the ability to determine the percentage of fragmentation on a particular volume. All the other features have been tested and are working fine but I’ve hit a snag trying to access this data. I would ideally prefer to use WMI as this matches the format I’m using for the other features but at this point I’m willing to use anything that can be efficiently integrated into the application, even if I have to use RegEx to filter the data. I am currently doing the development on a Windows 7 Professional (x64) machine. I have tested the following Powershell snippet using Administrator rights and it works flawlessly.
$drive = Get-WmiObject -Class Win32_Volume -Namespace root\CIMV2 -ComputerName . | Where-Object { $_.DriveLetter -eq 'D:' }
$drive.DefragAnalysis().DefragAnalysis
This is the method I’m using in C# to accomplish the same thing, but the InvokeMethod keeps returning 11 (0xB).
public static Fragmentation GetVolumeFragmentationAnalysis(string drive)
{
//Fragmenation object initialization removed for simplicity
try
{
ConnectionOptions mgmtConnOptions = new ConnectionOptions { EnablePrivileges = true };
ManagementScope scope = new ManagementScope(new ManagementPath(string.Format(#"\\{0}\root\CIMV2", Environment.MachineName)), mgmtConnOptions);
ObjectQuery query = new ObjectQuery(string.Format(#"SELECT * FROM Win32_Volume WHERE Name = '{0}\\'", drive));
scope.Connect();
using (ManagementObjectSearcher searcher = new ManagementObjectSearcher(scope, query))
{
object[] outputArgs = new object[2];
foreach (ManagementObject moVolume in searcher.Get())
{
// Execution stops at this line as the result is always 11
UInt32 result = (UInt32)moVolume.InvokeMethod("DefragAnalysis", outputArgs);
if (result == 0)
{
Console.WriteLine("Defrag Needed: = {0}\n", outputArgs[0]);
ManagementBaseObject mboDefragAnalysis = outputArgs[1] as ManagementBaseObject;
if (null != mboDefragAnalysis)
{
Console.WriteLine(mboDefragAnalysis["TotalPercentFragmentation"].ToString());
}
}
else
{
Console.WriteLine("Return Code: = {0}", result);
}
}
}
}
catch (Exception ex)
{
Console.WriteLine("Could not acquire fragmentation data.\n" + ex);
}
return result;
}
I have even added the following line to the app.manifest but still nothing.
<requestedExecutionLevel level="requireAdministrator" uiAccess="false" />
Could somebody please tell me what I’m overlooking? Failure is not an option for me on this, so if it cannot be done using C# I don’t mind creating a DLL in another language (even if I have to learn it), that will give me the results I need. Ideally the application should be able work on any OS from XP upwards and must be totally transparent to the user.
These are the resources I have already used. I wanted to add the jeffrey_wall blog on msdn as well but as a new user I can only add 2 hyperlinks at a time. Thanks again.
http://www.codeproject.com/Messages/2901324/Re-the-result-of-DefragAnalysis-method-in-csharp.aspx
http://social.technet.microsoft.com/Forums/vi-VN/winserverfiles/thread/9d56bfad-dcf5-4258-90cf-4ba9247200da

Try building your application targeting 'Any CPU' - on the Build tab of the project properties. I suspect you're using a target of x86. I get the same error code on my Win7 x64 machine if I do that.
In fact, running your PowerShell snippet in the x86 version of PowerShell gives an empty set of results, too.
You get the same error if you run either piece of code without full Administrator privileges, as you've found, so also ensure your app.manifest is correct. A UAC prompt is a handy hint that it's taking effect!
No idea why this WMI query doesn't like running under WoW64, I'm afraid, but hopefully this will give you a head-start.

You could simply call the PowerShell command you mentioned in your post, since you said the PowerShell code works. From C# you would want to follow this workflow:
Instantiate a PowerShell RunSpace
Open the RunSpace
Add a script to the Commands property
Invoke the command list
Here is an example of how to achieve this, and process the resulting object output.
http://www.codeproject.com/Articles/18229/How-to-run-PowerShell-scripts-from-C
For Windows XP and Windows Vista, you would have to ensure that PowerShell was installed on each of the systems you want to run your program on. Not a bad prerequisite to have, but something to keep in mind as a dependency.
Hope this helps.

The 32-bit WMI provider for Win32_Volume doesn't seem to be able to start the defragsvc for whatever reason. You can force the 64-bit WMI provider even in a 32-bit client running under WOW64 by changing your code to add an additional WMI connection option:
ConnectionOptions mgmtConnOptions = new ConnectionOptions {
EnablePrivileges = true,
Context = new ManagementNamedValueCollection() {
{ "__ProviderArchitecture", 64 }
}
};