Error 39: Mastercam X7-2022 Virtual Usb Bus

The is a critical driver issue occurring on Windows 10 and 11, primarily caused by Core Isolation (Memory Integrity) security features blocking the Virtual USB Bus driver . This error prevents Mastercam from verifying its HASP/NetHASP security dongle, essentially locking the software out of its license. Core Causes

Click in the top menu bar of Device Manager and select Add legacy hardware .

If the virtual USB bus registry keys become corrupted, Windows fails to initialize the driver stack. Press Windows Key + R , type regedit , and hit .

On Windows 11, a new security feature, "Memory Integrity," is often the cause of Code 39 errors for custom or non-signed drivers. This feature is part of Core Isolation and prevents drivers from accessing system memory in ways deemed unsafe. Mastercam X7-2022 Virtual Usb Bus Error 39

Check Device Manager to see if the Virtual USB device successfully initializes. 4. Clean Corrupted Registry UpperFilters and LowerFilters

A recent KB update may have patched the exploit used by older virtual USB emulators. Step-by-Step Solutions 1. Disable Memory Integrity (Core Isolation) This is the most frequent culprit in Windows 10 and 11.

Go to > Advanced options > Startup Settings > Click Restart . The is a critical driver issue occurring on

Use regedit to locate the Class key 36FC9E60-C465-11CF-8056-444553540000 and delete . Clears conflicting filter drivers that block the USB bus. Update Drivers

To avoid encountering Error 39 in the future during critical production windows:

If you've tried multiple versions (X7 and 2022 on one machine), remnants of old drivers can cause conflicts. Use a tool like CCleaner or manually scrub "Virtual USB Bus" entries from the registry. If the virtual USB bus registry keys become

Maintain a dedicated folder on your local drive containing the specific, working version of your USB runtime environment installers for quick recovery. If youg., Windows 10 Pro, Windows 11).

If Windows registers a corrupted class filter for USB devices, it will repeatedly trigger Code 39. Cleaning these filters forces Windows to rebuild the driver stack. Press Win + R , type regedit , and hit .

If you need to narrow down these steps for your setup, let me know: Your specific (Windows 10 or 11) Whether you use a physical USB dongle or a network license The exact Mastercam version giving you trouble right now