Microsoft this week released a beta version of what appears to be a very useful tool: An offline version of its Windows Defender anti-malware solution. This tool can help final and remove malicious software, much like the version built into Windows. But because it can be installed to CD, DVD, or USB flash drive, it can be run in offline mode, when the Windows OS isn't running. And that makes it more effective, since many exploits, like rootkits, are hard to remove when Windows is running.
You can find the Windows Defender Offline Beta on the Microsoft web site. You'll need a blank CD, DVD, or a USB flash drive you don't mind formatting. There are basically two downloads that need to occur; the tiny installer and then a later 214 MB Setup package that is expanded and copied onto the media. This package includes all the files needed to boot your PC plus the Windows Defender Offline tool itself.
To use the tool, you need to reboot your PC from the created optical disk or USB flash drive. (This could require interrupting the boot process and choosing a different boot device, of course.) The interface is straightforward and basically resembles a full-screen version of Windows Defender, giving you a chance to perform Quick, Full, and Custom scans of the underlying PC.
Intriguingly, this tool also appears to be based on the Windows 8 version of Windows Defender, in that it provides both spyware and anti-virus scanning.
Thanks to Aaron S. for the heads-up. This tool looks like a valuable addition to any PC troubleshooter's toolbox.