On Tuesday, Microsoft said Delta Air Lines was to blame for its battle to recover from a global cyber outage that resulted in it having to cancel over 6,000 flights.
The disruptions stranded hundreds of thousands of travelers and are estimated to have cost the airline $500M.
Ed Bastian, Delta’s CEO told CNBC last week that although the airline relied on CrowdStrike and Microsoft heavily, both companies had not delivered an “exceptional service.” He added that Microsoft’s platform was the “most fragile.”
Microsoft said it was still investigating the CrowdStrike event to understand why other airlines, including United and American, restored their operations fully much faster than Delta.
It did however add that its preliminary review indicated that Delta, unlike its rivals, had not modernized its IT infrastructure.
In a letter from an external lawyer, Microsoft called the airline’s comments misleading, false, incomplete, and damaging to the company and its reputation.
Microsoft said it had repeatedly offered to help Delta after the outage, but the carrier had declined. The tech giant added that Satya Nadella, its CEO, had emailed Bastian, but never received a reply.
It also accused Delta of using other technology providers’ services for its scheduling and crew-tracking system.
