Imagine allowing anyone to use your PC without supervision: your children, nephews and nieces, spouse's second cousin, or even your babysitter's boyfriend.
That's the promise of virtualization software such as the $25 Returnil Virtual System. The program creates a virtual PC for you or anyone else to operate in that's sealed off from your system files and personal data. I tried the beta of Returnil Virtual System 2010, which includes the Virtual Guard on-demand malware scanner.
Returnil is another security layer on top of your hardware and software firewall, real-time malware detector, and other security programs. Once enabled, no permanent changes will be made to your hard drive, except to the files and folders you specify beforehand.
The program's installation routine offers to perform a malware scan prior to loading the program onto your hard drive. The option to send to the company anonymous information about the malware it detects is selected by default, but you can choose to be prompted before any information is sent or to prevent any information from being collected or transmitted to the company.
After the installation completes, a toolbar is added to the desktop and an icon is placed in the notification area. Right-click the icon to hide the toolbar or the icon, enable or exit the program, or check for updates. Double-click the icon to open the main Returnil window. Here you can access the Virtual Guard antivirus scanner, System Safe virtual environment, and the program's other features.
After you register the beta—or the trial version of Returnil Virtual System 2008--you can specify files and folders that you can change while operating in a virtual environment. Otherwise, any changes you attempt to make to your hard drive while Returnil is enabled will disappear when you restart Windows. This includes the files you open, programs you use, Web sites you visit, and any other activity that would normally place or change data on your drive.
By default, Returnil uses half the available space on your hard drive to create its virtual environment. You can change this setting by clicking System Safe in the main Returnil window, choosing the advanced settings link, and selecting the System Safe tab. Use the slider control to reset the percentage of free hard-disk space allotted for the virtual environment, and click OK.
Other options let you password-protect the program, wipe all disk changes whenever you shut down Windows, enable protection when Windows starts, and assign a keyboard combination to open the program. I noticed a slight degradation in performance when Returnil's System Safe is enabled, but the slowdown was barely discernable on my 64-bit Windows Vista PC with 4GB of RAM and nearly 100GB of unused hard-drive space.
I experienced no problems using the beta, which is a 7.5MB download. Whether or not the addition of a malware scanner improves your PC's overall security, there's comfort in knowing that anyone—yourself included—can do just about anything on your PC without lasting effect. That's the peace of mind a virtual environment such as Returnil provides, and for little cost and only a modest performance hit.