A corrupt file led to the FAA ground stoppage. It was also found in the backup system

CNN —Officials are still trying to figure out exactly what led to the Federal Aviation Administration system outage on Wednesday but have traced it to a corrupt file, which was first reported by CNN. FAA officials told reporters early Wednesday that the issues developed in the 3 p.m. Officials ultimately found a corrupt file in the main NOTAM system, the source told CNN. During this early morning process, the FAA told reporters that the system was “beginning to come back online,” but said it would take time to resolve. The source said the NOTAM system is an example of aging infrastructure due for an overhaul.