Microsoft has released a confusing selection of security programs over the years. Deborah Armstrong asked me to make sense of them.
When it comes to security, the folks in Redmond can go overboard with new products--or worse, new names for old products. What follows is a complete list of Microsoft programs, past and present, intended to help keep malware off your computer.
At least, I think it's complete. If I missed anything, that's what the comment section is for.
Microsoft AntiSpyware: No longer available. You can think of this as an antivirus program that looked for spyware rather than viruses. Since modern antivirus programs also look for spyware, it was kind of redundant. It eventually became Windows Defender (see below).
Microsoft OneCare Live: No longer available. This utility and security suite included antivirus, backup, and other tools.
Windows Live OneCare Scanner: No longer available. This on-demand malware scanner was intended to supplement your regular anti-virus program by offering a second opinion when you felt you needed one.
Microsoft Windows Malicious Software Removal Tool: Another on-demand malware scanner, still available, but of limited usefulness. It's designed to remove a few specific, particularly stubborn threats. It's only updated once a month.
Microsoft Safety Scanner: Yet another on-demand scanner, although this time with a more comprehensive malware database. Safety Scanner is updated every ten days, which is better than monthly but still not frequently enough.
Microsoft Standalone System Sweeper: No longer available. Would you believe...another on-demand scanner? But this time, it's bootable, from either a CD or a flash drive. Bootable scanners are, arguably, the most effective kind.
Malware Prevention Diagnostic Tool: An entirely different kind of scanner. Instead of looking for malware, it checks how you've configured Windows and offers to fix settings that can be exploited by the bad guys.
Windows Defender: The renamed Microsoft AntiSpyware. It comes with Vista and Windows 7, but is usually turned off.
Windows Defender Offline: Another bootable scanner. Microsoft Standalone System Sweeper's replacement.
Windows Defender--the Windows 8 version: Like the two Windows before it, version 8 comes with Windows Defender. But this time, it uses the same antimalware engine as Security Essentials. In other words, it's a real antivirus program, but probably not one of the most effective.