Since old threads tend to get locked, not allowing more replies, let me say to anyone who comes here from a Google search:
It doesn't look like this problem is going to get solved. It looks like the Windows installation has to be scrapped and a new clean install from scratch has to be done, followed by reinstalling all applications and repeating all settings of all applications
etc.
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Here's the original question:
Microsoft Store and around a dozen other applications don't run. I tried a lot of things including doing an in-place upgrade from Windows 10 1903 to Windows 10 1903 keeping all files and apps. What it kept was the inability of these applications to run.
Start - Settings - Applications shows around a dozen unnamed applications attributed to Microsoft Corporation. However, Microsoft Store itself is not one of these. Microsoft Store is displayed in the list of applications, but doesn't have any size (not
0 bytes, but no size displayed at all), and was updated 2019/06/04.
The command wsreset gives an error message. The specified device, path, or file cannot be accessed. There is a possibility that the item can't be accessed because of a permissions problem. However, I've observed that the Windows folder doesn't contain
the subfolder needed by Microsoft Store. The in-place reinstallation of Windows 10 1903 did not create the necessary subfolders.
sfc /scannnow etc. also do not create the necessary subfolders.
This PC originally ran Windows 7 Pro Japanese and subsequently Windows 10 Pro Japanese. No other language version has ever been installed on this PC.

