First Look: Microsoft Security Essentials offers free and non-intrusive protection against malware

Microsoft's latest anti-malware application uses the same engine as OneCare, but is smaller, faster and more efficient than its predecessor

Microsoft's latest addition to its fleet of free applications, Security Essentials, is smaller, fast and efficient, but doesn't offer the wider range of features that security suites do.

The just-released beta of Microsoft Security Essentials is a solid, free tool that protects against malware while taking up few system resources and staying out of your way as much as possible.

This is set-it-and-forget-it software that handles the basic dangers, but doesn't try to compete with big-boy security suites such as those built by Symantec, McAfee or Panda. So you won't find extras such as a firewall, identity protection, anti-phishing technology or anti-spam. Instead, Security Essentials focuses on protecting you against viruses, spyware, rootkits and similar dangers, and does a very good job of it.

Those who have wrestled unhappily with the software's predecessor, Microsoft Live OneCare, will be pleased to know that Security Essentials suffers from none of the software bloat and slow performance that bedeviled OneCare. Unlike OneCare, Security Essentials doesn't do performance tune-ups, back up your PC, take up too much system resources -- or cost a penny.

Installation and setup

Security Essentials comes in versions for XP and Vista (the Vista version will also work with Windows 7). Both are light downloads: The 32-bit Vista download weighs in at 4.8 MB, the 64-bit Vista version at 3.8 MB and the XP version (there's only a 32-bit version) comes in at 7.6 MB.

Installation of the 32-bit Vista version on my machine took less than five minutes and was about as simple as an installation can be. There is one caveat, though: You need to have a validated copy of Windows. Not surprisingly, Microsoft's software won't work with pirated or non-validated versions.

Once installation is complete, the application downloads the latest anti-malware definitions. It then launches a quick system scan that took under ten minutes on my system.

Security Essentials uses a new feature called the Dynamic Signature Service, which employs a variety of techniques to check for malware even before that malware's specific signature has been identified. Microsoft says Security Essentials emulates the behavior of programs before they run, and uses the signature created during the process to look for any suspicious behavior or patterns of suspicious behavior, such as starting an unexpected network connection or trying to modify certain protected sections of Windows. The Dynamic Signature Service then determines what action to take against the potential malware.

Once the software has scanned your system, you don't need to do anything else, unless it finds malware that it wants to kill or quarantine. New anti-malware signatures are automatically downloaded daily, using the Windows Update engine; you can also have the software to check for the latest definitions manually. Security Essentials also provides real-time protection, so it watches your system as you use it and warns you if you're downloading malware or if your system has been infected. The software also scans your system once a week by default. You can manually override the defaults and set up specific days and times to perform the scans; more about this later.

Microsoft Security Essentials in action

Most of the time, you'll only know that Microsoft Security Essentials is running because you see its icon in the System Tray. Other than that, it leaves you alone unless it finds a problem. It uses very little RAM or system resources, and I noticed no performance hit on my machine when it ran, except when it performed a scan. When it started the scan, my PC slowed down for the first several minutes of the scan, but then ran fine with the scan working in the background.

Scans and updates are scheduled to run when your PC is idle, although you can run a scan manually. They are given a low priority by the operating system, further reducing their impact on your PC. In addition, CPU throttling is used to ensure that the software doesn't use more than 50% of your CPU.

When Security Essentials finds an infection on your system, you can have it immediately take action against the threat, or you can click Show Details, at which point you'll be shown as much information as the software has about the threat.

When you lick on the Clean Computer option, Security Essentials will either delete the file or quarantine it, depending on the nature of the threat.

Easy interface

Most of the time, that's all the interaction you'll have with Security Essentials -- there's very little need to open the program for any other reason. However, if you do open it to, for example, customize its actions in some way, you'll find a very simple interface that to a certain extent mimics the look of Windows Defender.

There are four tabs --- Home, Update, History and Settings. Home shows you the status of the software and your system and lets you perform a scan; Update shows you the status of definition updates and lets you update them manually; History shows you a history of the actions the software has taken.

Settings lets you change most aspects of how the program works, including when to perform scans, the type of scan to perform (Quick or Full), what actions to take when an infection is detected and the ability to exclude files, locations and processes from scans. There's actually little reason to change any of the defaults, although it's nice to know you can.

When customizing, keep in mind that a Full scan takes significantly longer than a Quick scan. On my system a Quick scan took under ten minutes; a Full scan took more than an hour.

There are anti-malware applications that offer far more customization than does Microsoft Security Essentials. Avast!, for example, lets you finely tune the sensitivity of its scans, so that you can make them more or less aggressive; you can't do that with Security Essentials. Most people won't miss it, but security tweakers may not be satisfied with the level of customization available.

How safe does it keep you?

Until Security Essentials is put through its paces by anti-virus labs, there's no definitive way to know how it stacks up against other applications. However, it shares the same engine and signatures as other Microsoft anti-malware products, including OneCare, the enterprise-focused Forefront and the monthly Microsoft Malicious Software Removal Tool. Therefore, looking at how OneCare compares should give some kind of guidance.

In its earliest days, OneCare did not perform impressively in anti-malware tests, but over time that has changed. It now ranks near the top of security software, according to the independent AV-Comparatives Web site. The site regularly tests anti-virus tools, and its latest tests of 16 applications, done in May, ranks OneCare as only one of three tools given the top Advanced+ designation (the other two were Kaspersky and ESET NOD32). It also tied for second place for its proactive detection of new malware and was the only software rated as giving very few false alarms.

The bottom line

In its reviewer's guide, the Microsoft says that "a surprising number of consumer PCs remain unprotected" against malware, although it offers no numbers. There are several reasons that consumers don't protect themselves, according to Microsoft. They are confused by the trial offers that come pre-installed on their PCs and by annual subscription fees. Heavy security suites slow down PCs and so people don't want to use them. Finally, some people simply aren't willing to pay for security.

Microsoft also notes that in "emerging markets," credit isn't always easy to come by, and so people can't pay for annual subscriptions using credit cards the way they do in countries such as the United States.

Given those goals, Microsoft Security Essentials -- even in beta form -- is a clear success. It's exceedingly simple to use, takes up few system resources and doesn't cost anything. Those who want fuller-featured security suites that do backups and other functions, or who want to be able to tweak their protection levels in more detail, will look elsewhere.

But apart from that, there's no reason not to download and use Microsoft Security Essentials (if you can -- apparently, Microsoft is limiting the number of downloads available). It does the job simply and for free.

This story, "First Look: Microsoft Security Essentials offers free and non-intrusive protection against malware" was originally published by Computerworld.

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