Mastercam is a popular computer-aided manufacturing (CAM) software used by machinists and manufacturers worldwide. The Virtual USB Multikey is a crucial component that enables users to run Mastercam on multiple computers with a single license. However, some users may encounter issues with the Virtual USB Multikey not working as expected. In this blog post, we'll explore common causes and provide a step-by-step guide to troubleshoot and resolve the issue.