According to the VirusScan USB product page, System Requirements;
It is available for a 30-day free trial on that page, if you want to experiment.
Your USB drive must use the U3™ platform. Please visit www.u3.com for more information about U3 smart drives.
If you are using Windows Vista™, a Vista-compatible U3 LaunchPad is required for your USB drive.
* Microsoft® Windows® 2000 Service Pack 4, Windows XP Service Pack 2, Windows Vista 32-bit
* Personal computer with Pentium-compatible processor 300 MHz or higher
* 128 MB RAM
* U3 USB smart drive with at least 25 MB free space (SanDisk® is McAfee’s preferred provider of U3 smart drives)
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