.Net Framework 4.8 WinForms apps on store

@StewartBW, Welcome to Microsoft Q&A,

what happens to the UWP File access permissions?

• WinForms apps packaged as MSIX retain more of their traditional full-trust behavior.
• By default, MSIX-packaged WinForms apps cannot access arbitrary locations on the file system unless you explicitly declare the required capabilities in the manifest.
• Your app might not be outright rejected unless it violates Store policies (e.g., accessing system directories without permission).

But when sideloaded the appx/msix version, it's not written there, but seems that it's handled internally/automatically by the store itself and it works, I just don't see where is saved?!

MSIX uses redirection and virtualization for certain system folders like AppData\Roaming and AppData\Local.

When your app writes to C:\Users\Admin\AppData\Roaming\Company\Product, MSIX redirects those writes to:

C:\Users\<UserName>\AppData\Local\Packages\<YourAppPackageId>\LocalCache

And based on my test, it indeed has some changes in the above path:

Hope my explanation could help you.

Best Regards,

Jack

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