Live updates: Follow the latest on the global IT outage
Several airports around the world issued warnings that travel could be disrupted as a result of the global IT outage.
The cause of the chaos, which has affected businesses from Australia to North America, is unclear, but several companies said problems with Microsoft were linked to a cyber security company called CrowdStrike.
Gatwick Airport in London warned passengers that services were "affected by the global Microsoft issues, so passengers may experience some delays while checking in and passing through security". Dublin Airport issued a similar statement.
Officials at Heathrow Airport assured travellers that flights were still operational.
"Microsoft is currently experiencing a global outage which is impacting select systems at Heathrow," a statement read.
"Flights are operational and we are implementing contingency plans to minimise any impact on journeys. Please check with your airline for the latest flight information."
Airlines including Vueling and Ryanair shared similar messages online, warning travellers of the possibility of delays.
In the UAE, flydubai assured passengers that its services had not been affected.
Etihad Airways said it was operating normally, but that passengers could be affected by "limited delays to services across its network", while Emirates confirmed there had been no impact on their flight operations.
"There may be delays to some flight timings later today, due to knock-on effects from delayed departures from some airports around our network," said an Emirates spokesperson.
Dubai Airports confirmed that Dubai International (DXB) was operating normally following a global system outage that affected the check-in process for some airlines in Terminals 1 and 2 on Friday morning.
"The affected airlines promptly switched to an alternate system, allowing normal check-in operations to resume swiftly," a Dubai Airports spokesperson said.
Indian carriers such as SpiceJet, IndiGo and Air India posted on X to inform passengers that there could be disruption to flights.
"Our digital systems have been impacted temporarily due to the current Microsoft outage, resulting in delays. We regret the inconvenience caused and request our guests to plan their travel accordingly," Air India said.
Aena, a company that looks after 46 airports in Spain, issued a statement saying operations were being dealt with manually. "Due to an incident in the computer system, alterations are occurring in the Aena systems and in Spain's airport network, which could cause delays," it said.
"We are working to resolve it as soon as possible. Meanwhile, operations are being handled manually."
In Sydney, airport officials told customers the chaos has affected operations. "A global technical outage has impacted some airline operations and terminal services," Sydney Airport said in a statement.
"Flights are currently arriving and departing, however there may be some delays throughout the evening. We have activated our contingency plans and deployed additional staff to our terminals."
Melbourne Airport said check-in procedures for some airlines had been affected.
Turkish Airlines, the world's largest airline by number of destinations, told passengers it was experiencing problems with ticketing, check-in and reservations due to "a global technical issue in our information systems".
The carrier advised passengers to follow its social media channels for updates.
From its hub in Istanbul, Turkish Airlines operates dozens of routes in the Middle East and North Africa, including Abu Dhabi, Dubai, Riyadh, Dammam, Muscat, Bahrain and Doha.
The company's website showed an error message this morning, advising users that the site was unavailable.
Turkish low-cost carrier Pegasus Airlines, which also flies to destinations across the Middle East, appeared to be operating normally on Friday morning.
