You have to specify the removableStorage capability in the app manifest file.To access files on the SD card, typically you have to specify the following things. Requirements for accessing files on the SD card When an app installed on the SD card saves files in its LocalFolder, however, those files are encrypted and are not accessible to other apps. When the SD card is removed from the device and opened from a PC, your files are visible in File Explorer and accessible to other apps.While the SD card is in the device, your files are accessible to other apps that have registered to handle the same file type.When an app saves files in a global location on the SD card, those files are not encrypted so they are typically accessible to other apps. However you can access the Documents library on the SD card by traversing the file system. Your app can't see or access the Documents library by using KnownFolders.DocumentsLibrary.

The Hidden attribute is typically used to reduce the risk of deleting data accidentally. Your app can't see files that are marked with the Hidden attribute.Your app can't see or access system folders and the files that they contain.

Your app can also create and manage folders.

Your app can only read and write files of file types that the app has registered to handle in the app manifest file.

What you can and can't access on the SD card What you can access You can store and access files on the optional SD card by using the following methods: Typically you also have to register to handle the type of files that your app stores and accesses.

In most cases, you have to specify the removableStorage capability in the app manifest file before your app can store and access files on the SD card. You can store and access non-essential data on an optional microSD card, especially on low-cost mobile devices that have limited internal storage and have a slot for an SD card.

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