my friend has an iPhone 5s with a cracked screen (probably not related). He sees in his notifications that he has messages (some texts, some iMessages) but when he opens messages, the entire screen goes white. He also can not send messages using Siri. It asks for the message to be sent but then displays that there is a problem. He can not go to a Genius Bar until Saturday and asked for my help. I got nothing. Any help would be appreciated.