Occurance : Air Canada B773 over Atlantic on Sep 26th 2014, blue screens

An Air Canada Boeing 777-300, registration C-FNNQ performing flight AC-870 from Montreal,QC (Canada) to Paris Charles de Gaulle (France) with 465 people on board, was enroute at FL340 near N53W41 when the crew declared PAN reporting the loss of all navigation systems. The aircraft continued eastbound, about 30 minutes later the crew reported the nav capability had been restored and cancelled the PAN. The aircraft continued to Paris for a safe landing on schedule. The Canadian TSB reported the crew declared PAN due to the loss of both flight management systems. The crew successfully rebooted both computer systems, cancelled the PAN and continued to their destination. Company maintenance determined the problem was attributable to the current software version of the FMCs, a new software release is expected in October 2014.