A cyber-scam network, which has infected more than eight million computers around the world in the past two years, has been shut down.
Microsoft and Symantec combined forces and closed down the hackers' network last week
The hackers used an online virus, known as the "Bamital Botnet", to gain access to personal details stored on PCs.
The botnet was used by criminals to access people's PCs and hijack online search results. It would then lead the user to an unknown website which could start downloading malware, steal their personal information or charge businesses for false online advertisement clicks.
It also led users to websites they never intended to vist. For example, one user was redirected from an official Norton Internet Security Page, which appeared in a list of search results, to a rogue antivirus website distributing malware.
Although exact numbers aren't known, Microsoft says more than eight million computers have been targeted with this virus in the past two years and 300,000 were disconnected this week from the network.
On 31st January Microsoft filed a lawsuit which was supported by Symantec to the botnet's operators to sever communication lines. This didn't happen, so data centres across the US were raided and the infected servers were disrupted.
Those computers which had been infected were then disconnected from the virus network. Users were directed to get rid of the virus.
This is the sixth time in the last three years that Microsoft has stopped a cybercrime network and the second in cooperation with Symantec.
"It was done in such a sneaky way that most victims wouldn't have even noticed a problem while the botnet was still operating," explained Richard Domigues Boscovich, assistant general counsel for Microsoft Digital Crimes Unit.
"Because the data gathered from this takedown will become part of Microsoft's ongoing research in support of protecting its customers from a range of evolving online security threats, we can actually use the criminals' infrastructure against them and make it harder and more expensive for them to commit cybercrime," he added.
How to disinfect your computer
Computers which are currently infected with the virus were contacted with a message from Microsoft.
It appeared when the user attempted to search for something on the internet and told the user their computer was very likely to be infected with malware which was redirecting the results of their search queries.
Two free programmes were then listed, Microsoft Safety Scanner and the Norton Power Eraser, which users were encouraged to run to disinfect their computers. More information on how to clear the virus from your computer can be found on the Microsoft Support website.
How to avoid cyber crime
The best way to avoid being hacked is to keep your computer's security systems up to date and regularly scan for infections. It's also vital to use different passwords for all the accounts you use online and to use a password which isn't likely to be hacked.
If your personal details have been stolen criminals can use them to get access to your accounts or apply for credit in your name. Therefore check your bank statements regularly and your credit record as this is where you'll be able to spot any irregularities.
If you do see something untoward, such as a payment you haven't authorised, call your bank immediately and let it know.