@Zachary Ralph,Thanks for posting in Q&A.
From your description, I know that you encountered an issue that disable Micrsoft store policy did not applied to all test machines.
Based on my testing, I did the same configuration as yours and it can work successfully. If you both configured "Turn off store application" and "Turn off store application (User)" settings, it will only apply to users. However, it is recommended that you configure one of them.
Please go to the targeted devices to check RemoveWindowsStore value in Registry.
Location: Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\WindowsStore.
0 means allowing access to Microsoft store, 1 means denying access to Microsoft store. If the RemoveWindowsStore value is 1 and user still can access the store, we suggest that you contact Windows Support to get more help and I will tag Windows on this thread.
Moreover, there are some alternative soulutions to disable the stroe:
• Disable Microsoft Store using Local Group Policy Editor
• Disable Microsoft Store using Registry
• Disable Microsoft Store using PowerShell
• Disable Microsoft Store on Windows using Group Policy
Please try above information, if there is any update, feel free to contact me.
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