Can't open Windows Defender?

I have a new laptop with Windows 10 (no S version) If I want to open windowsdefender or deactivate real-time protection in Windows settings, for example, I get the opportunity to open the Microsoft store and download a new app. However, it is then only said that no suitable app was found.

Very crisp: only fools turn off anti-malware software… And ITSec specialists for test purposes (but they don't ask here 😉)

You won't find any alternative antimalware programs in the MS Store because the providers don't publish them there.

You better look here:
http://www.bitdefender.de
http://www.kaspersky.de
https://www.sophos.com/de-de.aspx

These are the three providers that I can recommend without hesitation.

I don't want any alternatives. I just want to open windows defender. This works on my pc. Funnily enough not on the laptop. These virus services that behave like a virus do not get on my drive. Defender is enough…