UWP - Windows IOT - Getting files from a specific folder named "ad_runner" located in a USB drive

Question

I am having unhandled error show up when I am trying to access a file from a folder named "ad_runner" Which is located a USB drive. What am I doing wrong?

        async void AccessTheWebAsync()
    {
        StorageFolder remd = await KnownFolders.RemovableDevices.GetFolderAsync("ad_runner");
        IReadOnlyList<StorageFile> fileList = await remd.GetFilesAsync();
        foreach (StorageFile file in fileList)
        {
            dir_lbl.Text = dir_lbl.Text + "\r\n" + file.Name;
        }
    }

Answer 1

If you try to call await KnownFolders.RemovableDevices.GetFoldersAsync(); you can see that this first call don't return the folders inside removable devices but the removable devices themself. So, I modified a little your code to first retrieve all connected removable devices and, after this, checking for inside folder named "ad_runner":

async void AccessTheWebAsync()
    {
        //Maybe you want to do this inside a try catch and verify that at least 1 device is connected before you go on....
        var folderList = await KnownFolders.RemovableDevices.GetFoldersAsync();

        foreach (var device in await KnownFolders.RemovableDevices.GetFoldersAsync())
        {
            try
            {
                StorageFolder remd = await device.GetFolderAsync("ad_runner");
                IReadOnlyList<StorageFile> fileList = await remd.GetFilesAsync();
                foreach (StorageFile file in fileList)
                {
                    //Your logic here....
                   dir_lbl.Text = dir_lbl.Text + "\r\n" + file.Name;
                }
            }
            catch (Exception)
            {

            }
            await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
            {
                rightGridWrapper.Children.Add(new TextBlock { Text = $"DeviceName: {device.Name}" });
            });
        }
}