Open Settings (Windows Key + I)
Go to "Update & Security"
Select "Troubleshoot"
Click on "Additional troubleshooters"
Find "Windows Store Apps" and run the troubleshooter.
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Press Windows Key + R to open the Run dialog.
Type wsreset.exe and press Enter.
A command prompt window will open briefly, and then the Microsoft Store will launch automatically.
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Make sure Date and Time are okay.
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Open Command Prompt as administrator:
Type sfc /scannow and press Enter.
In the same Command Prompt window, type DISM /Online /Cleanup-Image /RestoreHealth and press Enter.
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Create a new user account to check.