Microsoft.ui.xaml.dll not found. Workarounds.

After a few days without working on a MAUI app, I returned to it today only to have it blow up on my face.

Loudly.

After a few searches online (and a VS2022 update to 17.12.1) I was, finally, able to, at least, have the debugger in VS 2022, to catch an exception.

The luck combination was from here, which states:

Workaround

2 available workarounds

1. Manually install the runtime that corresponds to the version you are using https://learn.microsoft.com/en-us/windows/apps/windows-app-sdk/downloads
   • MAUI 8.0.20+ is 1.5.2
   • MAUI 8.0.10-8.0.14 is 1.4.2
2. Set the project property in your MAUI app project. Ideally workaround 1 works for you. Disabling the DeploymentManager will cause some features of WinUI to no longer work.

<PropertyGroup>
     <WindowsAppSdkDeploymentManagerInitialize>false</WindowsAppSdkDeploymentManagerInitialize>
</PropertyGroup>

I tried the first one workaround, without success.

Then I tried the second one, with partial success: at least, now, my app deploys and the debugger engages, and it captured this exception:

The full description of the exception:

{System.DllNotFoundException}
Unable to load DLL 'Microsoft.ui.xaml.dll' or one of its dependencies: The specified module could not be found. (0x8007007E)

Stacktrace:
   at BatchSorter.WinUI.Program.XamlCheckProcessRequirements()
   at BatchSorter.WinUI.Program.Main(String[] args) in C:\Users\pauls\source\repos\FlinttsMints\BatchSorter.Maui\obj\Debug\net8.0-windows10.0.19041.0\win10-x64\Platforms\Windows\App.g.i.cs:line 29

So, it was in a generated code (therefore a code I didn’t write (phew -- I thought it was me).

Looking at this generated code, The only thing I found was this:

[global::System.Runtime.InteropServices.DllImport("Microsoft.ui.xaml.dll")]
[global::System.Runtime.InteropServices.DefaultDllImportSearchPaths(global::System.Runtime.InteropServices.DllImportSearchPath.SafeDirectories)]
private static extern void XamlCheckProcessRequirements();

Which doesn’t tell me much.

A couple more searches, led me to this question, which had a similar problem but in 2021.

Even so, one of the solutions, the one posted by X-Misaya, seemed to work, namely, add this property to the project file:

<WindowsAppSDKSelfContained>true</WindowsAppSDKSelfContained>

Now my application is not showing the images.