Understanding App Isolation Behavior in MSIX: Issue with System State Restoration After Crash

Question

We have Application built with .NET Forms, while the security components (DLLs) are developed in C++. Recently, we packaged our application using MSIX (App Isolation) and signed it with a self-signed certificate. The Application launches and functions as expected.

However, when we introduce an intentional crash (e.g., a null pointer exception), the system does not restore the changes made by the application, such as hiding the taskbar. Our understanding was that App Isolation would help revert any system modifications after a crash, but it seems this isn't the case.

Is this expected behavior for App Isolation in MSIX, or are we missing something in our configuration? Any insights on ensuring system state restoration would be appreciated.

Answer 1

How does the application act when not packaged and the intentional crash happens? That is how you should expect the application to run.

A packaged application not set to run inside an appcontainer has the same rights and almost the same environment as the application running without the package. One set to run inside an appcontainer has a lower integrity level but still almost the same environment. Understanding how packaged desktop apps run on Windows gives a description of how packaged applications run, and it does not state that an application running inside a package is unable to mutate the Windows OS state.

The previous text ignores Windows 11 24H2's updates which changes things a little, but even that doesn't prevent mutations to the OS state.