Windows 10: Windows 11: I try to deinstall an app, but the settings tell me "No way"!

Dear helpful Friends,A new laptop challenge every day: this might not be a life-threatening one, but I want to improve and keep my system clean.I try to deinstall an app - a small game installed not through Steam, MS App Store or any service, but straight to my hard drive.As shown in the screenshot, I am not able to click the "Deinstallieren" deinstall. The app was actually not shown in control panel programs list or in my 3rd party Uninstaller.I used another 3rd party Uninstaller to force it off the drive, but apparently parts remain....Please help me!With much appreciation,Chris

:)

 

Update requires deinstallion of Avira app that is not installed

Windows 10 wants to install an update on my computer, but it tells me that I have to deinstall the Avira Antivir app, first. The trouble is, I deinstalled that app one year ago (which was quite a hazzle. I had to download an Avira deinstallation app first, and do some operations in safe mode).
However, I do not see that app in my list, and I was sure up to now that the leech had gone, already.
How can I either make windows notice that the app is gone, or weed out the remains of Avira?

 

Why can't I deinstall the not / never needed Xbox, Cortana and OneDrive App from Windows 10

Hello,

I want to remove / deinstall the Xbox, Cortana and OneDrive App from Windows 10 from my business PC but in the "System\Apps & Features" dialog the Deinstall button is grayed out and OneDrive is not listed even in "Systemsteuerung\Alle Systemsteuerungselemente\Programme
und Features".

Thanks for the help,

 

Desktop HTML shortcuts being listed in Apps under settings?

A friends Win 10 installation is listing Desktop HTML shortcuts under Apps in the Setting App listing. Seems to have happened after he downloaded and installed a program in support of some two way radio equipment. System Restore does not correct the problem. Suggestions appreciated.