In the context of Mastercam X7, X8, X9, 2017, 2018, 2019, 2020, 2021, and 2022, this error almost always links back to the (often used for software-based licensing or network key emulation) or the official HASP/Sentinel driver layer. The underlying causes generally boil down to:
(That VID/PID is the virtual bus signature.)
Here is a comprehensive guide to troubleshooting and fixing the . Mastercam Virtual USB Bus Error 39 Fixed: A Complete Guide mastercam+x72022+virtual+usb+bus+error+39+fixed
Navigate to > Advanced options > Startup Settings > Restart . Press 7 or F7 to "Disable driver signature enforcement." Registry UpperFilters/LowerFilters Removal :
You might wonder: “My Mastercam 2022 worked fine last year. Why now?” In the context of Mastercam X7, X8, X9,
Open Device Manager → Show hidden devices. Under "System devices" appeared with a yellow exclamation. Uninstall it, and check "Delete driver software for this device."
Sometimes, Windows associates bad registry data with the Virtual USB controller class, causing permanent Error 39 states. Press Win + R , type regedit , and press . Press 7 or F7 to "Disable driver signature enforcement
Go to > Advanced options > Startup Settings > Restart .
Let me know in the comments. Good luck machining!
Then sign the modified INF using a self-signed certificate and add it to the Windows Trusted Publishers store (requires disabling Secure Boot temporarily).
Below is a comprehensive, step-by-step technical guide to permanently fix Error 39 and get your CAD/CAM environment back up and running. Understanding Why Error 39 Occurs