CNN  — 

Operations are gradually being restored but delays continue for a second day after “the largest IT outage in history” disrupted sectors across the globe, leaving thousands of passengers stranded at airports, emergency communication services down and blood donation centers without vital shipments.

Airlines, businesses, government agencies, health and emergency services, banks and schools and universities around the world ground to a halt or saw services disrupted due to a flawed software update for Microsoft Windows operating systems issued by the cybersecurity firm CrowdStrike, experts told CNN.

CrowdStrike’s CEO said a fix has been deployed, but experts say getting systems back in order will be a lengthy process.

The outage affected an estimated 8.5 million Windows devices, less than 1 percent of all Windows machines, according to a Saturday blog post from Microsoft. “While the percentage was small, the broad economic and societal impacts reflect the use of CrowdStrike by enterprises that run many critical services,” Microsoft said.

According to the tracking website FlightAware, more than 2,300 flights into, out of, or within the US have been canceled and more than 6,000 delayed, as of Saturday afternoon.

On Friday, more than 3,000 flights were canceled and more than 11,000 were delayed, according to FlightAware.com.

Worldwide, major airlines have said services are being restored.

A majority of United Airlines systems have recovered from Friday’s outage, the airline said in a statement.

“While most of our systems have recovered from the worldwide third-party software outage, we may continue to experience some disruption to our operation, including flight delays and cancellations,” United said.

Delta Air Lines is “continuing its operational recovery” after the outage prompted the airline to pause flying on Friday, according to a Saturday morning update. Still, over 600 Delta flights have been canceled Saturday.

“Additional cancelations are expected as some of Delta’s technology continues to recover from Friday morning’s vendor-caused issue,” the update said.

Jetstar Japan, Hong Kong Express and Cebu Pacific airlines said Saturday their operations are gradually being restored too.

Cybercriminals capitalized on the chaos by promoting fake websites filled with malicious software designed to compromise unsuspecting victims, according to warnings from the US government and multiple cybersecurity professionals.

Former McAfee CEO Dave DeWalt told CNN a group of private sector and government agencies worked overnight to “ascertain the threat” and find a solution to the global outage. The call included the Cybersecurity and Infrastructure Security Agency and other private and government organizations.

CrowdStrike CEO George Kurtz apologized to customers Friday for the outage and said the company is working with those affected.

“We understand the gravity of the situation and are deeply sorry for the inconvenience and disruption,” Kurtz posted on X. “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.”

But it could be easier said than done: Manual restarts of individual systems take time and expertise some customers don’t have, which is why companies have been slow to recover from the outage.

Chaos continues for travelers

Frustrated passengers lined up at airports backed up with flight cancellations and delays, some missing life events like funerals and birthdays. At Atlanta’s Hartsfield-Jackson International Airport, long lines of passengers waited for assistance Saturday, with many flights still canceled or delayed.

“I was supposed to be in California for my mom’s wedding,” Richard Whitfield of Pasco County, FL told CNN’s Isabel Rosales Saturday. Whitfield and his partner, Jonathan Shade, left Tampa on Thursday and missed their connecting flight in Atlanta due to poor weather conditions, delaying their landing and forcing the plane to refuel in Tallahassee.

After their rescheduled flight on Friday was delayed many times, the couple decided to cancel the trip and just head home. But with no available flights back to Tampa, Friday night, they spent their second night in an airport hotel. They were unable to get a voucher from Delta for either of their stays.

“(Richard has) been on hold for 24 hours,” Shade told CNN. “When he eventually got his number in line, it was 2,001.”

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Two hours later, Richard’s place in Delta Air Lines’ virtual customer service queue was 2,300 in line, Shade said. Delta Air Lines has reported the most cancellations, with more than 850 Delta and Delta Connection flights unable to depart.

“If we can’t do the flight, we will try for the car and if we can’t do the car, it’s just another night in a hotel and we will see what happens,” Shade said.

At last check, a rental car back to Tampa would cost the pair $600, Shade and Whitfield said. Amtrak is charging $1,000 for a one-way ticket to Tampa, they added.

Whitfield tells CNN the whole ordeal has had an impact on him. “For me, it’s been the domino effect that it has on humanity and everything that we need to survive: food, sleep, or water, housing,” he said.

Etienne Laurent/AFP/Getty Images
A traveler looks at a screen displaying delayed and canceled flights in Terminal 2, Delta Airlines, at Los Angeles airport, on Friday.

After spending 48 hours in Atlanta, they found a Saturday evening flight back to Tampa they say they can only hope is not delayed or canceled. For now, there is nothing the couple can do but wait and “get a good stiff drink,” Shade and Whitfield said.

In addition to the problems at airports, the outage has also caused delays at hotels and rental car companies. Major hotels, including Marriott International and some Hiltons, were impacted both in regard to payment processing and delays to check in-processes.

Even Americans not traveling felt the effects of the outage in various facets of their everyday lives, including while trying to call 911 during emergencies in some areas, getting or renewing their driver’s licenses or shipping or receiving packages.

There were reports of 911 outages in various states, like Alaska, and cities, like Phoenix, where the system was down for hours but has since been restored.

Driver’s license offices were closed or had limited services in Texas, Tennessee, North Carolina and Georgia.

Some hospitals had to cancel appointments and surgeries

While most hospitals remained open to treat medical emergencies, some said an inability to access electronic medical records and order lab tests and prescriptions had caused them to cancel patient appointments and surgeries.

Hospital workers scrambled to provide needed care to patients without the technology they rely on.

Kim Brown was near the end of her shift Thursday night as a labor and delivery nurse at Kaiser Permanente in San Jose, California, when the hospital’s computer systems, which it relies on to care for women in labor and their babies, went down.

“All of our babies get little plastic tags that will set off an alarm if they get too close to an exit or an elevator. That went down,” Brown said. “It was unnerving because we had zero information. It was just, ‘Oh, well, everything’s out now.’”

With the outage posing a security risk to newborn babies, the hospital called security guards to sit by the elevators to keep them safe.

At the postpartum care unit in Dignity Health California Hospital Medical Center in Los Angeles, nurse Laura Topete said she ran into a roadblock trying to get analgesic drugs for a woman who was in pain after delivery, but couldn’t access the doctor’s orders to see what kind of medications she could have.

“The patient was in pain longer than she needed to be,” Topete said.

Epic Systems, a company that makes widely used electronic health records systems for hospitals and doctors’ offices, said on Friday its Nebula cloud-based platform had been impacted by the outage overnight and some services, including telehealth visits, were not available during the outage. Another electronic medical records company, Veradigm, also said its systems were impacted by the CrowdStrike outage.

A spokesperson for the US Department of Health and Human Services said it was “working to assess the impact of the CrowdStrike outage on patient care and HHS systems, services, and operations,” along with federal, state, local and private sector partners.

In addition to hospitals, blood donation centers experienced challenges and altered blood shipment methods due to flight delays. New York Blood Center, which supplies about 200 hospitals in the Northeast, initiated an emergency driving operation to distribute collected blood. And Blood Assurance was concerned for its planned shipment of at least 20 platelets — the disc-shaped fragments that help with clotting — due to flight issues.

Government agencies were at a standstill

The impacts of the global tech outage were felt across the US as countless government agencies waited for services to get back to normal.

The mayor of Portland, Oregon, issued an emergency declaration due to the ongoing outage. It affected the city’s servers in city data centers, employee computers and single sign-on to cloud services, Mayor Ted Wheeler said in a news release.

In Southern California, the disruption caused connectivity issues at the Los Angeles County Superior Court and it temporarily limited jail bookings in San Diego County, officials said.

Elsewhere, some voting locations in Arizona experienced outages in Maricopa County as early voting continued in the state’s primary, according to the Maricopa County Elections Department. The county is the fourth-most populous in the US and is home to Phoenix, the county website said.

The Social Security Administration closed its local offices to the public on Friday after the outage shut down numerous services. The agency said in a statement it expected longer wait times for the national 800 phone number, and some online services may be unavailable.

CNN’s Mary Kay Mallonee, Josh Campbell, Brenda Goodman, Ramishah Maruf, Henry Klapper, Joe Sutton, Taylor Galgano, Brian Fung, Sean Lyngaas, Rebekah Riess, Dianne Gallagher, Shawn Nottingham, Kara Mihm, Isabel Rosales, Jaide Timm-Garcia, Christina Zdanowicz, Cheri Mossburg, Lauren Rapp, Chris Isidore, Isabel Rosales, Jaide Garcia, and Amanda Musa contributed to this report.