Doh! Buggy software helped cause blackout
That massive power outage across the northeastern U.S. and Canada last August was caused, at least in part, by a bug in an energy management software package
that prevented appropriate alarms from notifying power grid operators. Some folks had speculated the Slammer worm had something to do with the failure, but that's apparently not so:
Instead, the XA/21 bug was triggered by a unique combination of events and alarm conditions on the equipment it was monitoring, DiNicola said. When a backup server kicked-in, it also failed, unable to handle the accumulation of unprocessed events that had queued up since the main system's failure. Because the system failed silently, FirstEnergy's operators were unaware for over an hour that they were looking at outdated information on the status of their portion of the power grid, according to the November report.
Score one for the Luddites, I guess.