Can't access Mail or Mail setttings on iphone 4 + iOS 6.1.2 Since the upgrade to iOS 6, I've been unable to access my mail on wi-fi, cellular or disconnected. 

The symptoms are:


The mail button icon shows '1'
When clicking on te mail app icon, it attempts to open up the app, then it times out and goes back to the home screen
When clicking on settings -> Mail, Contacts, and Calendars, the phone gets stuck and times out then goes back to the home screen.
First, force-quit Mail.app. To do this: Go to your home screen. Double-click the home screen. Locate Mail.app in the bottom bar that appears. Press and hold Mail.app until the icons wiggle. Delete Mail.app from the bottom bar by clicking red X.

Try again to launch Mail. If this doesn't work, reset the iPhone by pressing and holding power and home buttons for 10 seconds. Restart device once it shuts off.