A number of major satellite operators said they were unaffected by the Microsoft outage on July 19 that created IT issues in multiple industries around the world and grounded flights. 

Intelsat, Eutelsat Communications, SES, Telesat, and Iridium Communications said in statements to Via Satellite they were not impacted by the Microsoft outage. 

Intelsat operates a fleet of around 50 Geostationary Orbit (GEO) satellites. Eutelsat operates a fleet of 35 GEO satellites and the OneWeb Low-Earth Orbit (LEO) constellation of more than 600 satellites. 

SES, which operates nearly 70 satellites in GEO and Medium-Earth Orbit, said in a statement it did not detect any material impact coming from the Microsoft 365 and CrowdStrike problems. “We will keep monitoring the situation to make sure there is no disruption to the services we provide,” an SES representative said.

Iridium said in a statement that it is not a CrowdStrike customer and its satellite network and internal functions continue to function normally.

Launch and satellite database Seradata, owned by Slingshot Aerospace, said that no impact on space systems has been reported. 

The outage was caused by a security update from cybersecurity platform CrowdStrike due to a defect in an update for Windows. Microsoft said in a statement that Windows machines using the CrowdStrike Falcon agent were impacted with on-premise and cloud applications including Azure, AWS, and Google Cloud.

CrowdStrike stressed in a statement that it was not a cyberattack. Mac and Linux hosts were not impacted.  CrowdStrike said it identified the issue and issued a fix 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,” CrowdStrike said in a statement. 

According to media reports, the outage stopped Delta Air Lines, American Airlines, and United Airlines flights. Certain banks and hospitals around the world and local government services in the U.S. and beyond reported impacts.

This story has been updated