7 Problems Y2K Actually Caused

Employees at the Niagara Mohawk Power Company control facility in Buffalo, New York, go through a round of Y2K testing toward the end of December 1999.
Employees at the Niagara Mohawk Power Company control facility in Buffalo, New York, go through a round of Y2K testing toward the end of December 1999. / Joe Traver / Getty Images / Hulton Archive

Remember Y2K? In the relatively early years of computer programming, many systems were designed to categorize dates by the last two digits of a year, ignoring the "19" at the start of the number to save memory space. That may have made computers work more efficiently, but it created a problem: What would happen when that date rolled over from 1999 to the year 2000—or “00”? Some worried that computers wouldn't know how to interpret an empty value for a year, and would read these dates as invalid, causing glitches around the world. Computer networks in use everywhere from the local McDonald's to nuclear arsenals were potentially running with the same vulnerability.

That was the apocalyptic reasoning behind the Y2K scare: The would-be computer cataclysm that was supposed to cripple banks and governments when the clock struck midnight on January 1, 2000. We know now that humanity came out of Y2K relatively unscathed, after spending an estimated $300 billion to $600 billion to fix potential problems in the years before the millennium. But still, a few issues did pop up—some caused a real headache, while others provided a bit of a laugh. Here are a few examples of the problems the Y2K bug actually did cause.

1. After Y2K, U.S. spy satellites stopped working for days.

The United States was one of the most proactive countries when it came to dealing with the impending Y2K bug. The nation as a whole spent at least $100 billion on fixes—with approximately $9 billion of that coming from the federal government. The intelligence and defense systems in the Pentagon got much of that funding (around $3.5 billion), but despite months of pricey computer patches and hardware overhauls, the government still had issues with important spy satellites for nearly three days after the new year. The feeds produced a stream of indecipherable information before the satellites were up and running again.

Three days may not seem too catastrophic, but one Pentagon official described the situation as a significant problem. Once the root of the problem was discovered, officials realized it wasn’t the bug itself that cut off communication; it was caused by the software patch that was designed to fix the issue in the first place. Oops!

2. On Y2K, some poor person got charged over $91,000 for renting The General’s Daughter.

Renting The General’s Daughter—the ho-hum 1999 military thriller starring John Travolta that was bound for the bargain bin—wouldn’t be anyone’s proudest moment. But one upstate New Yorker quickly found himself (and his taste in movies) making headlines nationwide, after the Y2K bug seemingly focused its wrath on the computer system of his local VHS rental store. The glitch erroneously reported that the man's copy of the tape was 100 years overdue and presented him a bill for over $91,250 on New Year's Day. The problem was quickly fixed, and the customer was given a free video rental for his troubles.

3. Japanese nuclear plants gave workers a scare during Y2K.

It’s bad enough to have to work on New Year’s Eve, but doing so in a nuclear power plant on Y2K, when apocalyptic rhetoric was coming to a head, must have been torture. And if that wasn't bad enough, just two minutes after midnight, alarms began going off. It happened at the Onagawa Nuclear Power Plant after computers picked up a problem with a device that measured the temperature of the surrounding seawater. The ordeal only lasted around 10 minutes before everything was corrected, and no serious issues were discovered.

Another similar event took place at the Shika Nuclear Power Station, after a "Y2K glitch" caused some of the plant’s alarm systems to go offline. Worst of all, a computer at a government office that monitors the plant at all times went dead along with the alarm system. There were other minor hiccups like this around Japan, but all were immediately contained and corrected. Officials at the time would not confirm if all these events were even directly linked to the Y2K bug or were just standard, momentary glitches.

4. The U.S. Naval Observatory was temporarily out of step during Y2K.

A look inside the U.S. Naval Observatory in Washington, D.C., on December 29, 1999.
A look inside the U.S. Naval Observatory in Washington, D.C., on December 29, 1999. / Michael Smith / Getty Images / Hulton Archive

The U.S. Naval Observatory’s whole job is to be on time; the agency was established in 1830 to care for the country’s navigational instruments and evolved into becoming the official timekeeper of the United States. So you can understand how embarrassing it was for the agency’s website to declare the date as January 1, 19100 in the early hours of Y2K. Though the Navy would call it a “black eye,” the issue was fixed less than an hour after it was initially reported.

5. Y2K caused a newborn to be registered as 100 years old.

One of the most common Y2K problems had to do with computers being unable to recognize people's ages accurately. In Denmark, the country's first "millennium baby" got an auspicious start to life when the hospital's computers originally registered it as 100 years old. Then the computer system for the German opera company, Deutsche Oper, automatically reverted its dates back to 1900 on January 1, 2000. This caused all the ages of employees and their children to be taken from the last two digits of their birth year, meaning someone born in 1990 would be classified as 90 years old. This temporarily prevented employees from collecting child subsidies from the government normally included on their payroll, since, according to the opera company's computers, mothers and fathers of young children were now the parents of bright-eyed and rowdy nonagenarians.

6. A lot of people were stuck with Y2K survival kits.

Taking advantage of the apocalyptic fears surrounding Y2K, plenty of companies released all manner of “Y2K survival kits” in the months leading up to the supposed doomsday. This soon became a multi-million-dollar industry, with one company, appropriately called Preparedness Resources, raking in $16 million by selling supply boxes made up of dehydrated food, water purifiers, battery-free flashlights, blankets, and waterproof matches. The real preparedness came from Scott Sperry, Preparedness Resources's president, who instituted a “no return” policy on all the kits he sold.

7. Y2K made one man in Germany a temporary millionaire.

In Germany, the Y2K bug was the prime suspect in the case of a man who suddenly found himself quite a bit wealthier in January 2000. Apparently his bank account had randomly been credited about $6 million, with the date on the transaction reading December 30, 1899. Officials at the time weren't sure if the millennium glitch was responsible for the man's sudden cash flow, but his good fortunes likely didn't last long.

Plenty of other issues involving banks, hospitals, transit authorities, and other agencies occurred, but most were just temporary nuisances that were barely notable enough to make the local news. After all, Hotmail displaying the year as "3900" for a few hours isn't exactly enough to get people rioting in the streets.

While the Y2K panic now is usually thought of as an overreaction, the lack of any real issues might have been because of the hundreds of billions of dollars poured into the fixes in the years beforehand. In an interview on CNN, Bill Gates said that Y2K "ended up being a fairly minor issue because people really worked together. If people had ignored the thing then we would be seeing the real impact."