SEOUL — South Korea is renowned for its digital innovation, with coast-to-coast broadband and a 4G LTE network that reaches into Seoul’s subway system. But this tech-savvy country is stuck in a time warp in one way: its slavish dependence on Internet Explorer.

For South Koreans who use other browsers such as Chrome or Safari, online shopping often begins with a pop-up notice warning that they might not be able to buy what they came for.

“Purchases can only be made through Internet Explorer,” says one such message on the Web site of Asiana Airlines, one of South Korea’s two major carriers.

In much of the world, Internet Explorer, initially developed by Microsoft in the 1990s, has faced fierce competition from browsers developed by Google and Apple. IE is bashed by tech snobs as a Black­Berry-like bygone.

Internet Explorer’s fall has been profound enough that its own video ads have poked fun at its image as “ancient” — but it argues on its Web site browseryou­lovedtohate.com that the latest versions, IE 9 and IE 10, are vastly improved and give the company a shot at “browser redemption.”

But South Koreans remain captive to laws passed 14 years ago, which — in the name of Internet security — require citizens to bank and make nearly all purchases with Internet Explorer. Three-quarters of the country’s Web usage involves Internet Explorer, according to a measurement by the Web analytics firm Stat­Counter — among the highest in the world. Internet Explorer is nearly as much a part of a South Korean computer as the screen itself.

“Internet Explorer has bugs. It freezes. It requires all these annoying updates,” said Lee Dong-won, a 35-year-old businessman.

“But everybody I know uses it,” said Seo Yeon-ho, a 25-year-old design student.

Only the daring stray from Internet Explorer — and when they do, they need to come up with some other way to shop and pay bills online. Those with computers that run Windows have no problem; even if they otherwise browse through Chrome or Firefox, they can double-click on IE when it’s time to make purchases.

But those with Apple computers — for which IE isn’t available — have it harder. Some go to Internet cafes. Some rely on their office desktops. Some dash into hotel business centers. Some hold on to their old computers and boot them up when it’s time to make purchases. Still others depend on a secret weapon called Boot Camp, a software program that allows a Mac to run Windows.

“Just look at this,” one salesman said at an Apple reseller in downtown Seoul, demonstrating on a laptop that he pulled out from behind the help desk.

All it takes to buy a plane ticket on an Apple computer in South Korea, he said, is the $70 special software and a $250 copy of Windows 7.

“No problem,” he said, smiling.

Security concerns

The story of how South Korea became dependent on Internet Explorer begins in the late 1990s.

South Korea’s government was among the first to encourage shopping and banking online, but many people were concerned about Internet safety. The government’s goal was to make Internet shopping nearly as secure as a trip to a small-town market, one where vendors know all their customers by name and face.