Have you verified the install version? Despite the system installer saying it's on, here's how to check from powershell
Run PS in admin mode, and copy and paste this w/o quotes:
"Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -Recurse | Get-ItemProperty -Name version -EA 0 | Where { $_.PSChildName -Match '^(?!S)\p{L}'} | Select PSChildName, version"
Your return should look like what's in my screenshot. If it all returns properly, then it might be damaged files or broken associations. Try running the .net repair tool which you can find here:
You must be registered to see the links
then see what happens.