Mastercam+x72022+virtual+usb+bus+error+39+fixed

Error 39 is a Windows kernel-level PnP (Plug and Play) error. It doesn't mean "license expired." It means: Windows sees a device (virtual or physical), loads a driver, but the driver tells the OS, "I can't start. Something is wrong with the hardware or its configuration."

In Mastercam's case, the "hardware" was a virtual USB bus—a software-emulated USB controller created by the license manager (typically SafeNet / Sentinel HASP). The physical USB dongle plugged into a real port, but the HASP driver created a virtual bus inside Windows, then mounted the dongle's cryptographic keys on that bus.

Why?

After the Windows 11 update (or a Windows 10 22H2 cumulative update), Microsoft tightened driver signature enforcement and changed how USBHUB.SYS and Winusb.sys interact with virtual root hubs. The HASP driver—signed with a SHA-1 certificate from 2012—was now considered "untrustworthy."

Windows loaded it but refused to start the virtual bus device. Error 39. mastercam+x72022+virtual+usb+bus+error+39+fixed

This usually occurs after a Windows Update (specifically updates blocking unsigned drivers) or a security software quarantine. Windows 10/11 has gotten aggressive about blocking older virtual drivers that Mastercam emulators rely on.

Published by: CAD/CAM Troubleshooting Lab
Target Software: Mastercam X7, X8, X9, 2017, 2018, 2019, 2020, 2021, 2022
Error Code: Code 39 (Windows Device Manager – Virtual USB Bus Driver) Error 39 is a Windows kernel-level PnP (Plug and Play) error

If Error 39 persists, the specific vusbbus.sys file shipped with Mastercam 2022 or X7 is corrupted or incompatible with your Windows build. Solution: Replace it with a known-working version.

Why this works: Windows may have cached a corrupted driver signature database. Manually replacing the file bypasses this cache. After the Windows 11 update (or a Windows