Major reasons why a user might not be able to download apps via Windows Store are as follows:
The required app might not be compatible with your system
The system you are trying to download an app on might be outdated. If it is older than the oldest version the app can run on, Windows Store will not allow you to download the app.
Family safety settings hide apps
Windows Store blocks some apps because not all apps should be accessible to children. The Family Safety settings can be turned on if your family accesses your machine and if this setting is on, Windows Store will hide buy button from all apps that should not be accessed by children.
System was not restarted after being updated
If you have recently updated your system and did not restart it, Windows Store will not let you download any app. Updates get integrated and functional after you restart your system.
Required app is not available in the country you are trying to download
Not all apps are available in all countries. Some might be available worldwide, while others have restrictions based on geographical locations. Windows Store will not show you buy button on apps that are restricted in the country you are trying to download them. To solve these issues, you can try methods listed further in the writing. One of these methods will definitely work in resolving the problem.
Method 1: Set system date and time
It is possible that the date and time set in your system is not according to the time zone of your location. Windows Store will not show you apps that are restricted in the country your system is following the time zone of. Right click on the clock and choose Adjust date/time or a similar option that would allow you to adjust the time. Make sure the time is correct.
Method 2: Clear cache for Windows Store
Open the Run Dialog by hitting Windows + R. Type WSReset.exe in the dialog that opens and click OK.
This simple step will clear the cache of the store and you will be allowed to download apps if there was a problem.
Method 3: Restart your system
As aforementioned, your system might not have been restarted after some updates being made; hence, the issue in downloading apps from Windows Store. To restart, press the Windows key on your keyboard and click on Power. From the list that opens, click on Restart.
Method 4: Microsoft Accounts Troubleshooter
If nothing else works, there might be some problem with the Microsoft account you are logged in with on Windows Store. Run Microsoft Accounts Troubleshooter from here and let it fix the problem.
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