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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!

WinForms WebBrowser HtmlDocument.Write behaves differently in different solutions

Recently, my application has crashed when trying to display a rather lengthy (but otherwise simple) HTML e-mail.
The crash was caused by mshtml.dll getting a stack overflow (exception code 0xc00000fd). Of note here is that this didn't throw an exception but it actually just crashed the program as a whole. The error was retrieved from the Windows event log.
In the process of debugging, I created a smaller sample solution to try and narrow down the issue. However, not only does it work fine in the sample solution, it behaves completely different from the main program despite running the same code even for the simplest of HTML strings.
The code is as follows:
var webBrowser1 = new System.Windows.Forms.WebBrowser();
webBrowser1.AllowNavigation = false;
webBrowser1.AllowWebBrowserDrop = false;
webBrowser1.Navigate("about:blank");
var doc = webBrowser1.Document.OpenNew(true);
doc.Write("<HTML><BODY>This is a new HTML document.</BODY></HTML>");
var count = doc.All.Count;
var html = doc.All[0].OuterHtml;
In the sample solution this evaluates to:
count = 4; // [HTML, HEAD, TITLE, BODY]
html = "<HTML><HEAD></HEAD>\r\n<BODY>This is a new HTML document.</BODY></HTML>";
Meanwhile in the main program it comes out to:
count = 3; // [HTML, HEAD, BODY]
html = "<html><head></head><body>This is a new HTML document.</body></html>";
These are small discrepancies but that is largely due to the simple HTML used. The one that causes the crash has rather significant differences.
I am absolutely stumped as to how the result can be so vastly different.
The documentation for HtmlDocument.Write(string) states that:
It is recommended that you write an entire valid HTML document using the Write method, including HTML and BODY tags. However, if you write just HTML elements, the Document Object Model (DOM) will supply these elements for you.
But I have no idea how the DomDocument is provided nor why they would be different in the first place. Both solutions are running in x64 Debug mode and Net-Framework 4.6.2.
Both load the module: C:\WINDOWS\assembly\GAC\Microsoft.mshtml\7.0.3300.0__b03f5f7f11d50a3a\Microsoft.mshtml.dll
How is it possible that these produce different results?!
Any and all help welcome.
Thanks in advance.

The difference in behavior stems from the registry entry as proposed by Jimi and linked here
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\FeatureControl\FEATURE_BROWSER_EMULATION
To reiterate, in the above registry the main program had an entry "ApplicationFileName.exe"=dword:00002af9 while my new test-application didn't.
This, in and for itself, does not explain the crashing of mshtml.dll itself but since the question was about the difference in behavior I'll post this as the answer. The crash is most likely linked to the outdated version used by Visual Studio but I haven't yet had the chance to look into some of the proposed fixes for that.

Revit API - Exception thrown: 'Autodesk.Revit.Exceptions.InternalException' in RevitAPI.dll - When trying to run button twice

Objective
Hi All, I'm working on making a button in Revit that is meant to add a single viewport to a new sheet and then change the viewport to show a viewTitle instead of being empty or just a line
Error
When I run the button for the first time, everything works except the view title is not set to the loaded family although the view title "line" is showing. My error occurs when I run the button the second time.
This is the error I get when I try to run the button a second time:
Exception thrown: 'Autodesk.Revit.Exceptions.InternalException' in RevitAPI.dll
A managed exception was thrown by Revit or by one of its external applications.
The error occurs at this line :
Viewport newViewPort = Viewport.Create(doc, viewSheet.Id, duplicatedPlan2Copy, new XYZ(location.U, location.V, 0));
Exploration
From what I've researched, the button is trying to access an element that is already being accessed but if I'm changing the scale, I should be able to change the ViewTitle. See references at the bottom of this question
here is some of my code which is in the transaction
FamilySymbol firstSheet = colTitleBlocks.FirstElement() as FamilySymbol;
ViewSheet viewSheet = ViewSheet.Create(doc, firstSheet.Id);
UV location = new UV((viewSheet.Outline.Max.U - viewSheet.Outline.Min.U) / 2,
(viewSheet.Outline.Max.V - viewSheet.Outline.Min.V) / 2);
ElementId duplicatedPlan2Copy = duplicatedPlan.Duplicate(ViewDuplicateOption.WithDetailing);
Viewport newViewPort = Viewport.Create(doc, viewSheet.Id, duplicatedPlan2Copy, new XYZ(location.U, location.V, 0));
Findings
I've found that if I remove this line from my code:
bool elementType = doc.GetElement(newViewPort.GetTypeId()).get_Parameter(BuiltInParameter.VIEWPORT_ATTR_LABEL_TAG).Set(viewTitleIdCommand);
It works and is able to create new sheets and place viewports with the view title line only repeatedly.
Any and all help is appreciated.
This link here shows how having 2 separate transaction commits solved the problem however I tried it and that didn't work. this one shows something similar
Here is a reference to my other related question regarding the button

I suggest that you explore and test your intended functionality manually through the user interface first. Once that is stable and optimised and works as expected, you can move over to automating the same steps programmatically through the Revit API. That will probably help you understand what the problem is in a much more efficient manner than struggling with the API, which just replicates the UI functionality.

I've figured it out. I was initially trying to using the TitleView's elementId loaded in from my LoadFamily class that I had instead of finding the elementId through a Filtered Element Collector.
I'm not sure why that was throwing me an error but it was.

LineSeries.cs not found

I am trying to create a graph with C# and the WPF chartingToolkit, I have the following code:
LineSeries lineSeries1 = new LineSeries();
lineSeries1.Title = region;
lineSeries1.DependentValuePath = "Value";
lineSeries1.IndependentValuePath = "Key";
lineSeries1.ItemsSource = points;
this.Graph.Series.Add(lineSeries1);
where points is a Dictionary<string, int> created in earlier code. This code compiles fine and runs fine until it reaches the line LineSeries lineSeries1 = new LineSeries();. Upon reaching this line it throws a Source Not Found: LineSeries.cs not found exception. I have tried putting it as System.Windows.Controls.DataVisualization.Charting.LineSeries lineseries1 = new System.Windows.Controls.DataVisualization.Charting.LineSeries(); but that failed to fix the issue. Everywhere I look for examples of how to do this it is written exactly how I have it.
EDIT:
It works perfectly without the debugger. The problem only exists with it.

The debugger was looking for a source file but was not able to find it. This will have been either because you don't have it available or because the version of the source you have does not exactly match the version which was compiled into your library.
If the latter is the case, you can work around it by going to Tools -> Options -> Debugging and unchecking the "Require source files to exactly match the original version" option.

Why is PictureBox.Load locking image on some systems?

(Please see the edit on the bottom of the question, if you do not want to read the whole story.)
Hi,
I am new to stackoverflow. Don’t get me wrong, I use it quite often. But up until now I never actually posted something. This is because I did not have something new/useful to say and my English is not that good. The first thing (might have) changed, the latter did not.
I ran into a problem at a customer's Windows 7 system quite recently. I was shipping a C# .Net 4.0 Windows Forms application via ClickOnce. Basically, it is an application that creates a bitmap file and shows it to the user. If the bitmap exists prior to the creation, the existing file gets deleted first. After that the new file is created and loaded by a PictureBox.
The following thing occurred at the customer’s system: After starting the application the first creation succeeds – the second and all following ones do not. The file cannot be deleted, because some process is blocking it. This process is the application itself.
System.IO.IOException: The process cannot access the file “filename” because it is being used by another process.
Well, of course that is nothing unusual. The thing is I tested the application on several systems. None showed this exception. And until now I am unable to see an code error.
So I looked a little bit closer on the customer’s system: The only difference I could find is, that they changed the users folder so that they are not located on the windows partition, but on a different one (C:\Users --> D:\Users). I searched for an instruction on the internet and did the same thing on one of my test systems. To my surprise I got the same exception when I ran my application on it.
With that I could change my code so that the exception does not occur anymore. But I do not understand why that is. So maybe there is something wrong with my code and the error just reveals itself under that special circumstances. Or maybe the code is okay and the reason lies somewhere else. I just hoped that you might be able to help me.
So here is some code I put together, that shows the same behavior. I used 3 buttons, an OpenFileDialog and a PictureBox on a Form. First thing to do is to choose an image file. By pressing one of the two remaining buttons it gets copied into the main folder of the application. After being copied it is shown by the PictureBox. By the way, it does not seem to matter if it is a ClickOnce-application or a “normal” one.
String m_FileName;
private void btnChooseFile_Click(object sender, EventArgs e) {
if(openFileDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK) { // If file was chosen, set file name for later use and activate buttons.
m_FileName = "Test" + Path.GetExtension(openFileDialog1.FileName);
}
}
private void button1_Click(object sender, EventArgs e) {
// This is not working.
if(this.pictureBox1.Image != null) {
//Image img = this.pictureBox1.Image; // I was not sure, if maybe the pictureBox somehow prevents the disposing of the image, as long as it's assigned to it.
//this.pictureBox1.ImageLocation = null; // So I set them null, both the image and the image location.
//this.pictureBox1.Image = null;
//img.Dispose(); // Then I disposed the image.
this.pictureBox1.Image.Dispose(); // The short version. It is not working either way.
this.pictureBox1.Image = null;
}
(new FileInfo(openFileDialog1.FileName)).CopyTo(m_FileName, true); // But still this is where the Exception occurs.
this.pictureBox1.Load(m_FileName);
}
private void button2_Click(object sender, EventArgs e) {
//This is working.
if(this.pictureBox1.Image != null) {
//Image img = this.pictureBox1.Image;
//this.pictureBox1.Image = null;
//img.Dispose();
this.pictureBox1.Image.Dispose();
this.pictureBox1.Image = null;
}
(new FileInfo(openFileDialog1.FileName)).CopyTo(m_FileName, true);
pictureBox1.Image = Image.FromFile(m_FileName);
}
What happens now is the following: If I start the application and click button1 twice, I will get the exception (on the second click). If I start it and click button2 twice, I will not. If I start the application and click buttons1 first and after that button2, I will get the exception. So, the Picture.Load-Function somehow blocks the file, even if I dispose it.
When I searched on the internet, I found an article from microsoft: http://support.microsoft.com/kb/309482/en-us. But it does not hit the bull's eye.
Take into account, that both versions are working on all my test machines. I just get the exception when I change the users folder to a non-windows-partition.
Why is that? And where is the difference in the presented versions?
Edit
Okay, because of the first and only reaction so far, it seems to me, that it is still not clear, what really happens: If I take the above code, put it in a Windows Forms application, compile it and run it on different computers (at work, at home, does not matter) it works - both button1 and button2 (with the Click-functions linked to them) can be used as often as I like - no exception thrown. If I run the application on a computer, where I changed the users folder, and click button1 the second time - bam - IOException, file locked by process. Button2 works as long as I do not press button1.
The first answer implies, that I should get the locking on every system. But I DO NOT (as long as I do not change the users folder)! I tested it on every single computer I could get my hands on - no IOException. I set up a new system, just to rule out some special changes to the systems in my company - both buttonx_Click functions worked - no exception either. I even compiled the program on another computer - same behavior. The only three systems to throw that exception were the ones with the changed users folder.
So far I have no clue, why this difference in behavior occurs. Can somebody help me?
Anybody?

Yes, this is normal. Happens on any operating system, doesn't have anything to do with the Users folder location. The PictureBox.Load() method was intented to be used to load images from locations other than the file system. Like a web site. Which is slow, it avoids freezing the UI while the download is taking place.
It internally uses a FileStream when it discovers that the url you pass is actually a file and not a website name. This FileStream does not get disposed until the PictureBox itself is disposed or you call the Load() method again. A requirement because Image.FromStream() requires the stream to remain readable until the image is no longer used. It is this FileStream that keeps a lock on the file. Disposing the PictureBox.Image is not enough to also dispose the FileStream, the Image object doesn't know that it is being displayed inside a picture box.
There are several ways to solve this problem:
Use the Image property instead of Load(), assign it from Image.FromFile(). Disposing the Image now also releases the lock on the file. As you found out
Keep a dummy image around, one that perhaps displays a "Loading..." bitmap. Load() it first to release the lock on the file
Dispose the PictureBox and recreate it.

This works and unlocks the file
Image img= Image.FromFile(mypath);
Graphics g = pictureBox1.CreateGraphics();
g.DrawImage(img,0,0);
img.Dispose();