Last year, Microsoft announced that it was halting development of its highly regarded Windows Live OneCare product (see my review of Windows Live OneCare 2.0) and would instead release a free anti-malware solution codenamed Morro by the end of 2009. Morro, of course, became known as Microsoft Security Essentials (MSE), and as promised it is absolutely free and available to all genuine Windows XP, Vista, and 7 users, and will come in both 32-bit and 64-bit variants (32-bit only on XP).

Put simply, MSE is OneCare minus the stuff that's not related to fighting malware. It doesn't have a managed firewall, can't manage a "circle" of computers on a home network, doesn't help prevent applications from putting icons in the system tray at boot-up, and doesn't have any online photo backup capabilities. What it does have, however, is all good stuff: MSE is small, fast, light, and effective, and since it's built on the same award-winning underpinnings as Microsoft's other security products you know you can trust it. I've been using it since well before the public beta, and I've found it to the be a near perfect security solution.

Let's take a closer look.