Microsoft Security Essentials is designed to protect Windows computers from "viruses, spyware, and other malicious software," Microsoft said. It replaces Windows Live OneCare, a paid subscription security and PC optimization package that the company discontinued earlier this year after it failed to catch on.
"Consumers have told us that they want the protection of real-time security software but we know that too many are either unwilling or unable to pay for it, and so end up unprotected," said Microsoft security general manager Amy Barzdukas, in a statement.
"With Microsoft Security Essentials, consumers can get high-quality protection that is easy to get and easy to use—and it won't get in their way," said Barzdukas. The product runs in the background and issues alerts if it detects a security threat.
Microsoft constantly updates the service's malware detection capabilities so it can keep up with the latest threats. To do so, it relies on Dynamic Signature Service, a new Microsoft technology that keeps users' PCs up to date in real-time without requiring new downloads.
Microsoft says it's in its own interest to offer free security software because doing so will help keep the Windows environment free of viruses. But competitors may see the move as a sign that Microsoft may be looking to dominate yet another market by bundling new products with Windows.
It's not immediately clear to what extent Microsoft will push Security Essentials—formerly codenamed Morro--as the default antivirus service on new Windows 7 PCs, which hit stores Oct. 22nd. The company in the past has found itself in regulatory hot water by tying other products too closely to the Windows OS.
European antitrust authorities previously slapped Microsoft with more than $1 billion in fines, in part for bundling Windows Media Player with Windows. Microsoft was ultimately ordered to produce a version of Windows for the European market that does not include WMP.
Microsoft Security Essentials is available in eight languages and 19 countries, the company said. It runs on Windows XP SP2 and all later versions of Windows, including Vista and Windows 7.
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