Microsoft Security Essentials review

In use, Security Essentials is visible only as a little "fortress" icon in the system tray which glows green if you're up to date, or red if your computer is, for any reason, unprotected. It's more low-key than AVG's free antivirus package, and a lot less intrusive than the free edition of AntiVir, which nags you every day to upgrade to the paid-for version.

And since there's so little to the program, its impact on your PC is low. On our test system it didn’t add a single second to boot time, though it did continue to hit the CPU for seven seconds after the desktop had appeared. And it added just 120MB to our system’s overall RAM footprint, making it a very light program by security suite standards.

This last point is, we think, what makes Security Essentials a success. Individuals and businesses alike are often saddled with relatively low-specification machines, not to mention limited budgets. Security Essentials, being a free, minimal package, assuages both these concerns.

For that reason, it has a real chance of making it onto machines that would otherwise be unprotected — and thus of having a real impact on the spread of malware.

If you're half-way through a subscription to a paid-for security system, there's no immediate reason to leap to Security Essentials. The extra warnings and defence mechanisms offered by something like Kaspersky or Norton do have a value. But if you have one or more PCs that are currently unprotected there's really no good reason not to install Security Essentials.