Let’s start with the following quote from the Microsoft website, “The Microsoft Malicious Software Removal Tool does not replace an antivirus product. It is strictly a post-infection removal tool. Therefore, we strongly recommend that you install and use an up-to-date antivirus product.”
Very good advice. Installing and updating antivirus should be the first task in any computer setup, and regular checks of its status should become routine.
That said, it’s also a good idea to periodically run this tool, or one like it, to check your system for bugs that might sneak by. Many similar applications are available, and one that is very effective (and very free) is Malwarebytes.
A simple Run command offering quick access to the MWMSRT in XP, Vista, or Windows 7 was found in an extremely helpful article by Lori Cline, Mega List of Run Line Commands.
To find this tool with the Run command, hold the Windows key and tap the R key (Win+R). Then, in Run, type mrt and hit the Enter key or click OK.
In Vista or Windows 7, this will more than likely bring up the dreaded UAC (User Account Control) warning. Just click Continue.
In the MWMSRT dialog box, click Next. The links to documentation and the malicious software list will help answer questions about this tool. However, if you pass those by, you should at least click Protect Your PC, which links to the Microsoft Safety and Security Center.
In the next step, three scan types are offered, Quick, Full, or Customized. The Customized scan provides an option to scan specific folders. Just click the radio button next to Customized scan and click the Choose Folder button. In the Browse For Folder dialog box, you can scroll through the entire system and choose a single folder to scan. For more information about scanning individual files or folders, see the tip, Scan Individual Files for Viruses.
A Full scan took a couple hours on my machine, but the number of files on the computer will determine scan time. Scan results include a list of the types of malicious software that the scan is designed to remove, and links to further information about each type can be found in the Malware column of the detailed results dialog box.
If, for some reason, this tool didn’t come pre-installed on your computer, or if it has been removed, it can be downloaded for free here.