"Could not sign in x-apple-md-action_message" when signing in to App Store I was trying to download a game from the App Store on my iPhone 5c (iOS 8.4) and I put in my password to download it but I got a pop-up message on my screen saying this: "Could not sign in x-apple-md-action_message". What does this mean?
This error occurs when a connection cannot be established.  To fix it, try the following:


Sign out of the App Store


Go to Settings > App and iTunes Stores
Tap your Apple ID and tap Sign out

Shut down your iPhone
Restart your iPhone
Sign back into the App Store with your Apple ID.