First, ironies out of the way. What triggered a wave of Microsoft computer crashes was an update from Crowdstrike, a popular software security firm, which was supposed to protect software and put a temporary stake through its heart.

The result disrupted flights, affected banks, and took many companies offline, including some popular commercial real estate sites.

Crowdstrike chief executive officer George Kurtz in part wrote on a social media post on Friday, "We understand the gravity of the situation and are deeply sorry for the inconvenience and disruption. We are working with all impacted customers to ensure that systems are back up and they can deliver the services their customers are counting on."