Clickonce Deployed WPF Desktop App Crashes

I have deployed a WPF Windows desktop app that targets .NET Framework 4.6.1. Over a dozen users have installed it on their Win 10 PC's and the app installs and runs without issue. The app is signed with a code-signing certificate which is working fine. There is no unmanaged code in the app.

On one Win 10 PC the app installs without error and even starts (displays sign-in screen) without error. But as soon as the user signs-in, when the main window is about to open, the app crashes and disappears from the screen.

I've managed to copy the following error message, and I have the Windows .wer file, but the contents of are not helpful and I can't work out what is causing the error or how to fix it.

Faulting application name: samadhi.exe, version: 1.0.0.0, time stamp: 0x5f8d1af0
Faulting module name: clr.dll, version: 4.8.4250.0, time stamp: 0x5f2a0630
Exception code: 0xc0000005
Fault offset: 0x0010409c
Faulting process id: 0xb40
Faulting application start time: 0x01d6a8fc436df911
Faulting application path: C:\Users\mongk\AppData\Local\Apps\2.0\DQL38KV8.XQ5\ZK547QA9.7LW\sama..tion_ee5134a9f21f5a9c_0001.0000_5a8f16833951b6e5\samadhi.exe
Faulting module path: C:\Windows\Microsoft.NET\Framework\v4.0.30319\clr.dll
Report Id: 3aca7880-67c2-44f3-9943-074e5e522d56
Faulting package full name: 
Faulting package-relative application ID: 

Application: samadhi.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an internal error in the .NET Runtime at IP 7270409C (72600000) with exit code 80131506.

Error message says: "The process was terminated due to an internal error in the .NET Runtime". However, I've tried the following, but none of these actions have fixed the problem:

• re-installed .NET Framework
• ran .NET repair
• cleared .NET cache
• reinstalled the app
• checked Windows is up-to-date