No more support

The first Windows XP version hit the market in 2001. Today, it's a dinosaur among operating systems in the fast-moving Internet world. But the great-grandfather of Windows 8 - Microsoft's newest system software - is still wildly popular: in Germany alone, it's estimated that between 11 and 20 percent of all computers still use XP.

Worldwide, XP is installed on about one third of all computers, and the very fact that the system is still commonly used all over the world makes it a global risk.

Since its launch, Microsoft has released about 100 security updates every year to protect the operating system against attacks, but as of Tuesday (08.042014), Microsoft has ended all technical support for Windows XP - which means there will be no more security updates.

Like a Swiss cheese

When Windows XP was developed 13 years ago, certain security standards didn't even exist, so Microsoft released regular updates to patch old and new security holes, automatically and free of cost.

Ending support has sweeping consequences for users, says IT expert Andreas Marx.

"In just a short period of time, Windows XP will be full of holes like a Swiss cheese," he says, "holes that hackers and other attackers can use."

Criminal hackers are always trying to infiltrate computer systems with malware, including viruses, worms and so-called Trojans which can be downloaded when surfing the Internet or opening an e-mail attachment. Once opened, the malware installs itself on your computer, allowing hackers to operate it remotely by ferreting out passwords and sending emails from their own computers, possibly even committing crimes.

Up to a quarter of a million computer viruses come into circulation every day - that's three per second. Entire industries are specialized in cybercrime, and Marx says they're raking in billions of euros: "These globally active criminal organizations are just waiting for security gaps like the ones that will open up on Windows XP." He says there's already been a surge in attacks on XP computers lately.

Too risky

Norbert Pohlmann of the Institute for Internet Security in Gelsenkirchen says it will be risky to access the Internet using an XP computer from Tuesday onwards: "If I continue to use XP, I'm not only endangering myself because my computer can be attacked and my data can be stolen, but I'm also endangering others."

When criminals place malware on a computer, it can be used to attack other computers, too.

"People are being negligent," says Pohlmann, "if they don't change over to a new operating system now."

Some European governments are trying to buy time before they make the move to a new operating system. They have struck deals with Microsoft for Customer Support, guaranteeing them technical help for a little while longer. But the missing updates for Windows XP could prove to be a huge security risk in developing and emerging countries, where the old system is even more popular and widespread than in industrialized nations.

"In China, for instance, about 70 to 80 percent of all computers run on XP," says Andreas Marx. In countries such as India, many people use the software because it has low system requirements and still runs superbly on a ten-year-old computer.

Marx says there is another reason why XP is so popular: copy protection wasn't as advanced as it is today when XP came out, so there are masses of bootleg copies of the software - free and without a license.

Global danger

But is the financial incentive big enough for criminals in poor countries to launch major attacks on old XP computers? Norbert Pohlmann says that's not the issue.

"If access to other people's computers is really easy for them, that is risky for us all," he warns - the more computers they can access, the more havoc they can create. "Criminal gangs could use computers in emerging markets to attack computers in Europe."

But he says there should have been a global campaign warning of the upcoming security holes in Windows XP months ago.

According to Marx, though, no matter how big the risk, some users have yet to be convinced that they need to change. "The point is," says Marx, "many people say their Windows XP works fine, so why should they shell out a lot of money to buy a new operating system?"