How do I sign in to Store?

I generally don't use anything store-related, but the other day I wanted to try a new theme and I realized I can only get them through Store. But I can't get them through Store since it wants me to sign in and refuses to give me any way to do that. If I click "signin" I get this error



The only thing I can find in Google is that this error might be firewall-related. But I checked, i did not forbid the Store to do anything, it can update itself and the apps already installed.

I am using Windows on a local account, but I can't see why should that be a problem (and no, Windows is not "better" if I sign in with the Microsoft account). Or is it?

Brink said:

Hello,
You might see if resetting the Microsoft Store app may help if it's some sort of glitch.
Reset App in Windows 10

This did not work. The powershell command didn't work somehow, it complained about unknown option or something, but I was able to reset the app from settings. Unfortunately, this did not change anything.

These services are up and running.

I have also tried the Troubleshooter, as suggested in one of the pages that @dalchina suggested (other methods are not very helpful). This is what I got



So, does it mean that one cannot sign in just into Store, without using the Microsoft account to sign in into Windows?

Ah, so maybe that's the problem. I don't have an option to add a Microsoft account there, just work or school account.



What could have I done to cause this?