Thousands of computer users around the world received startling news Wednesday when they tried to search online: their PCs were infected and used by hackers to commit cybercrime.

The news came after Microsoft disrupted a network of infected computers Wednesday that was helping cyber criminals commit fraud. In this case, hackers had installed malicious software on computers to steal victims' personal data and hijack search results to charge businesses for online advertisement clicks. By taking down the cybercrime ring, more than 300,000 people around the world will regain control of their computers, Richard Boscovich, a senior attorney at Microsoft's Digital Crimes Unit, said in a blog post.

"What’s most concerning is that these cybercriminals made people go to sites that they never intended to go to, and took control of the computer away from its owner," Boscovich said. The malicious software was used "in such a sneaky way that most victims wouldn’t have even noticed a problem while the botnet was still operating," Boscovich added.

The infected computers were part of what is called a botnet, or a global network of infected PCs that grows in size as computer users accidentally click on a bad links, files or websites and their computers begin performing automated tasks that help cyber criminals commit identity theft and other types of fraud.

Microsoft received a court order on Jan. 31 to sever all the communications between the hackers and the infected PCs, which were part of the so-called Bamital botnet. On Wednesday, Microsoft – escorted by the U.S. Marshals Service – seized evidence about the cybercriminals from web-hosting facilities in Virginia and New Jersey.

As a result of Wednesday's takedown, thousands of victims whose PCs were infected were temporarily unable to search online, Microsoft said. Their browsers were re-directed to a website that showed them how to clean up their infected computers before they could search again.

The cybercriminals behind the botnet remain unknown, but investigators believe they came from Russia or Eastern Europe because code on the infected PCs contained a Russian phrase that said "I was already here," Boscovich said.

Microsoft worked with the security firm Symantec to help disrupt the botnet. It was the sixth time in three years Microsoft had taken such action to go after cybercriminals.

Microsoft has an interest in combating cybercrime. Its Windows operating systems still dominates the market, and the company is trying to keep its customers secure online.

Last March, Microsoft, joined by a team of United States marshals, raided offices in Pennsylvania and Illinois to disrupt a global network of more than 13 million infected computers that they said helped cyber criminals steal $100 million. In that case, the computers were infected with the so-called Zeus malware that could record users' computer keystrokes to steal usernames and passwords linked to online bank accounts.

Earlier on HuffPost:

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  • 'It Is Undercooked'

    <a href="">Gizmodo's Sam Biddle</a> had plenty to praise for the Surface RT -- for its design, its version of Internet Explorer -- before listing a litany of flaws and recommending not buying it. Wrote Biddle: <blockquote>We're not there yet. Surface is a fantastic promise, and holds fantastic potential. But while potential is worth your attention, it's not worth your paycheck. Surface RT gets so many things right, and pulls so many good things together into one package. But it is undercooked.</blockquote>

  • 'Yes, You Can Use It As Your Only Computer'

    Like Biddle, <a href="">Wired's Mat Honan</a> complained about typing difficulties and lack of apps, but overall was pleased. <blockquote>Yes, you can use it as your only computer. I would never have made that claim about an iPad or Android tablet. But if you only need to live in Microsoft Office and the web and e-mail, and use your computer for media consumption, you’ll do great with this. I used it as my primary computer for several days. There were applications I missed, and I would never want it to be my only computer (the keyboard and screen are just too small) but it worked. I was fine.</blockquote>

  • 'A Brilliantly Conceived Machine Whose Hardware Will Take Your Breath away — But Whose Software Will Take Away Your Patience'

    <a href="">The New York Times' David Pogue</a> laments the "split personality" of the tablet: It's hardware is beautiful, it's software is heartbreaking. "In time, maybe the Windows RT apps will come. Maybe the snags will get fixed. Maybe people will solve the superimposed puzzle of Windows RT and Windows 8," Pogue writes hopefully. "Until then, the Surface is a brilliantly conceived machine whose hardware will take your breath away — but whose software will take away your patience."

  • 'A Slate Upon Which You Can Get Some Serious Work Done'

    <a href="">Engadget's Tim Stevens</a> makes another distinction: Between those who want a tablet to create or to consumer. The former, he says, will want to look closely at the Surface RT. From Stevens' review: <blockquote>The Microsoft Surface with Windows RT's $499 starting MSRP means those thinking about making the investment here will be carefully cross-shopping against same-priced offerings from Apple, ASUS and others. Where does this one rate? Very well -- but very differently. While those devices are primarily targeted at content-hungry consumers, the Surface is a slate upon which you can get some serious work done, and do so comfortably. You can't always say that of the competition.</blockquote>

  • 'Surface RT Isn’t A Tablet'

    Ultimately concluding that consumers should wait out this generation of Surfaces until Microsoft does some improvements, <a href="">TechCrunch's Matt Burns</a> argues that this really isn't a tablet: "It’s not a legitimate alternative to the iPad or Galaxy Note 10.1. That’s not a bad thing," he says. "With the Touch Covers, the Surface RT is a fine alternative to a laptop, offering a slightly limited Windows experience in a small, versatile form. Just don’t call it an iPad killer."

  • 'Surface Is The Most Flexible Tablet I've Ever Used'

    <a href="">Tech blogger Anand Shimpi</a> called the tablet "recommendable" in a generally positive review. He writes thus: <blockquote>Surface is the most flexible tablet I've ever used. Through two seemingly simple additions to the design (but incredibly complex to actually develop and implement), Microsoft took a tablet and turned it into something much more. If you're frustrated by productivity limits of currently available tablets, Surface really seems to be the right formula for a solution. </blockquote>

  • 'It May Give You The Productivity Some Miss In Other Tablets'

    <a href="">The Wall Street Journal's Walter S. Mossberg </a>argues that if you can look past the flaws (mediocre battery life, poor app selection) buyers who want productivity out of their tablets should consider the Surface RT. "Microsoft's Surface is a tablet with some pluses: the major Office apps and nice, optional keyboards," he writes. "If you can live with its tiny number of third-party apps, and somewhat disappointing battery life, it may give you the productivity some miss in other tablets."