Hi Murray,
Upon checking from my end, it seems that SmartAssembly is an obfuscator that helps protect your application against reverse-engineering or modification. It could be that this tool is used by the current app that you're using or other apps in your PC.
I suggest that you perform a clean boot, and then check the status of the issue. If the issue persists, check Programs & features and check if it is a program that you can uninstall. Below are articles for your reference:
- How to perform a clean boot in WindowsNote: Refer to the Reset the computer to start normally after clean boot troubleshootin g section afterwards.
- How to properly uninstall programs
Your reply is most important for me to assist you accordingly.