Is it possible to run a .NET core 3.1 app on Windows 7 Embedded?

Question

I am trying to run a .NET Core 3.1 WPF application on a Windows 7 Embedded VM. Unfortunately, Windows 7 Embedded does not officially support .NET Core. Is there a workaround to get this to work anyway?

I have already tried publishing the app as a self-contained package, and as a single file (which is also self-contained), hoping that this would include all the necessary dependencies. But unfortunately, this didn't work. The event viewer showed me this exception:

Message: Failed to load the dll from (path)\hostfxr.dll, HRESULT:0x80070057
The library hostfxr.dll was found, but loading it from (path)\hostfxr.dll failed
- Installing .NET Core prerequisites might help resolve this problem.
  (download link)

But of course that installer does not work on Windows 7 embedded ("This update is not applicable to your computer").

Is there a way to manually include all necessary dependencies, to get this to load anyway?

Answer 1

I had the same error regarding hostfxr.dll while starting from a barebones Windows 7 installation. Microsoft lists a specific security patch that fixed the error once I installed it.

KB3063858

64-bit: https://www.microsoft.com/download/details.aspx?id=47442
32-bit: https://www.microsoft.com/download/details.aspx?id=47409

.Net 5/Core Dependencies
https://learn.microsoft.com/en-us/dotnet/core/install/windows?tabs=net50#dependencies

.Net 5/Core Dependencies