This error message has been reported from time to time over the years, and it's usually some sort of a one-off error. Have you tried shutting down and restarting a few times to see if it eventually clears? If it's consistently repeatable, use the email form on this page (http://www.iflygps.com/Support/Get-Help) or the phone number there during office hours. If they can't help you immediately, they'll walk you through the process of sending a log file for further troubleshooting.
This error typically indicates some corruption either on the SD card or in the firmware. Flashing the OS might fix it, or forcing an udate to the aviation app might fix it. Best to contact support for this error.