Nokia Lumia 820 - I have stalled on the App downloads while restoring a saved backup on my Nokia Lumia phone, each indicating Attention required (error 8000ffff). What can I do?

The restoration procedure tries to download and install app entries from the App List. This error may occur when an app has been removed from Store and no longer available to be installed or updated. To clear a list of the failed apps:

  1. Go to Store, tap on the screen where it shows number of downloads waiting.
  2. Tap and hold on each of the stuck downloads, then select Cancel to delete them one at a time.
  3. Apply this for the all stalled app downloads.