Mastercam X72022 Virtual Usb Bus Error 39 Updated May 2026
Before we fix the problem, it helps to know why it happens.
The Mastercam Virtual USB Bus is a kernel-mode driver that allows the NetHASP (hardware key) to communicate with Mastercam via USB. Error 39 explicitly states that Windows has identified the device, but the driver is either corrupted, blocked, or incompatible.
Many users report Error 39 when they have both Mastercam X7 (HASP) and Mastercam 2022 (CodeMeter) installed on the same PC. The two licensing systems conflict.
Updated Solution for Hybrid Installations:
If you must use a local USB dongle for 2022, you cannot keep X7 on the same machine. You must use a Virtual Machine (VMware or VirtualBox) with Windows 8.1 for X7 and your host OS for 2022.
Mastercam, a leading Computer-Aided Manufacturing (CAM) solution, relies on hardware-based licensing mechanisms (USB security dongles) to authorize software usage. To interface with these dongles, the software installs specific virtual bus drivers and USB filter drivers.
Windows Error Code 39 is a Device Manager error message generated when the operating system cannot load a device driver for a piece of hardware. The error message typically states:
"Windows cannot load the device driver for this hardware. The driver may be corrupted or missing. (Code 39)"
In the context of Mastercam X7 through 2022, this error specifically targets the Virtual USB Bus component. This failure is often precipitated by operating system updates, conflicting software installations, or—most commonly—the remnants of previous software protection drivers left behind during updates or uninstallations.
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If the registry fix does not resolve the issue, perform a clean install of the licensing drivers:
Virtual USB Bus Error 39 in Mastercam (X7 through 2022) typically occurs because Windows security features block the loading of older or virtual drivers, often flagging them as "corrupted or missing"
. This is frequently linked to virtual dongles or MultiKey emulators used for software licensing. Top Recommended Fixes Disable Core Isolation (Memory Integrity) mastercam x72022 virtual usb bus error 39 updated
: This is the most common cause on Windows 10 and 11. These systems block drivers that do not meet strict security requirements. Windows Security Device Security Core isolation details Memory integrity Restart your computer. Registry Modification (UpperFilters/LowerFilters)
: Corrupted registry entries can prevent USB controllers from loading correctly. Registry Editor ) as an administrator. Navigate to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\36FC9E60-C465-11CF-8056-444553540000 On the right side, find and UpperFilters LowerFilters entries if they exist. Restart your PC. Reinstall Mastercam/HASP Drivers : Sometimes the driver installation itself is faulty. Completely uninstall the existing HASP or Aladdin drivers.
Download and install the latest versions directly from the official Mastercam support Check for Corrupt User Profile
: In some cases, repeated crashes while multiple Mastercam instances are open can corrupt the Windows User Profile. Creating a new Windows user account and testing Mastercam there may resolve the issue. Google Groups
: For those using virtual "MultiKey" or similar emulators, these are often incompatible with modern Windows updates unless specific 64-bit patches are applied or digital signature enforcement is disabled. disable driver signature enforcement to see if that allows the virtual driver to load? Mastercam X7-2022 Virtual Usb Bus Error 39 - Google Groups
The "Virtual USB Bus Error 39" in Mastercam (typically related to
emulators) is often caused by modern Windows security features blocking unsigned or incompatible virtual drivers. Matsusada Precision Primary Fix: Disable Core Isolation
The most frequent cause of Error 39 on Windows 10 and 11 is the Memory Integrity setting within Core Isolation , which prevents many virtual USB drivers from loading. Matsusada Precision Windows 10/11 Windows Security (search via the Start menu). Navigate to Device Security Core Isolation details Memory integrity your computer for the change to take effect. Registry Modification (Upper/Lower Filters)
If the driver is still showing as "corrupted or missing" (Code 39), you may need to clear corrupted registry filters. back up your registry before making changes. Search for and open (Registry Editor). Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\ Locate the key 36FC9E60-C465-11CF-8056-444553540000 (Universal Serial Bus controllers). In the right pane, look for UpperFilters LowerFilters . If they exist, your system. Alternative Solutions How to Fix USB Error Code 39 In Windows 10/8/7 [Tutorial]
The "Virtual USB Bus Error 39" in Mastercam (X7 through 2022) typically occurs when Windows cannot load the driver because it’s corrupted, missing, or blocked by security features like Core Isolation. The Story of the Ghost in the USB
Marcus stared at his screen, where a deadline for a critical milling job loomed. He’d just upgraded his workstation to Windows 11, but instead of the sleek performance he expected, Mastercam X7-2022 refused to launch. In the Device Manager, a yellow exclamation mark mocked him next to the Virtual USB MultiKey. Before we fix the problem, it helps to know why it happens
"The driver may be corrupted or missing. (Code 39)," the error read.
He tried the usual dance: unplugging the HASP dongle and moving it to a different port, but the error remained. He dug into the Mastercam user forums and found his first clue: Core Isolation.
The First Fix: Breaking the ShieldMarcus opened Windows Security, navigated to Device Security, and clicked on Core Isolation details. He flipped the Memory Integrity switch to Off and restarted his PC.
Upon reboot, the yellow exclamation mark was gone, but Mastercam still wouldn't budge. He realized his Windows User profile might have become corrupted after a previous crash while running multiple instances of the software.
The Final Fix: The Registry CleansingDetermined, Marcus opened Regedit. He navigated deep into the system's class settings:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\36FC9E60-C465-11CF-8098-00AA004C324E.
On the right, he found the culprits: UpperFilters and LowerFilters. He deleted them, closed the registry, and performed one final reboot. This time, as the desktop loaded, the HASP light flickered to life. Mastercam launched smoothly, and the "ghost" in the USB bus was finally laid to rest.
Fixing the "Virtual USB Bus Error 39" in Mastercam (versions X7 through 2022) usually involves
resolving a conflict between the driver and Windows security features or clearing corrupted registry filters Matsusada Precision 1. Disable Core Isolation (Memory Integrity)
The most common cause of Error 39 in Windows 10 and 11 is the Core Isolation
security feature, which blocks older virtual USB drivers like MultiKey or older Sentinel HASP drivers from loading. Matsusada Precision Start menu and search for Windows Security Device Security Core isolation details Memory integrity your computer. Matsusada Precision 2. Update Virtual USB/HASP Drivers
Ensuring you have the latest driver can sometimes bypass the need to lower security settings. Matsusada Precision Download the latest Sentinel HASP LDK Runtime from the official Thales (formerly SafeNet/Gemalto) support page Uninstall existing drivers via Device Manager
(under Universal Serial Bus controllers) before installing the new version. Microsoft Learn 3. Clear Registry "UpperFilters" If you must use a local USB dongle
If the error persists, corrupted registry entries may be preventing the driver from loading properly. , and press Enter. Important: Back up your registry by going to File > Export before making changes. Navigate to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\36FC9E60-C465-11CF-8056-444553540000 On the right side, look for UpperFilters LowerFilters . If they exist, right-click 4. Fix via "DeviceGuard" Registry Key
For some Windows 10/11 updates, you might need to manually disable the Hypervisor-enforced Code Integrity via the registry if the standard UI toggle doesn't work. Microsoft Learn In the Registry Editor, go to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\DeviceGuard\Scenarios\HypervisorEnforcedCodeIntegrity your system. Microsoft Learn manually reinstall the MultiKey virtual driver specifically for Mastercam? How to Fix USB Error Code 39 In Windows 10/8/7 [Tutorial]
Virtual USB Bus Error 39 in Mastercam (X7 through 2022) typically occurs because Windows Security features , specifically Core Isolation (Memory Integrity)
, block the virtual driver from loading due to compatibility or digital signature issues Core Solutions to Fix Error 39 1. Disable Core Isolation (Most Common Fix)
Modern Windows security prevents many virtual USB drivers from loading. Disabling this feature often restores functionality immediately. Matsusada Precision Windows 11: Privacy & security Windows Security Device security Core isolation details Memory integrity Windows 10: Update & Security Windows Security Device Security Core isolation details Memory integrity your computer for changes to take effect. Matsusada Precision 2. Modify the Windows Registry (Advanced)
If the driver is corrupted by existing filter entries, deleting them can clear the error. , and run as Administrator. Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\ Locate the key 36FC9E60-C465-11CF-8056-444553540000 (Standard USB Class). In the right pane, find UpperFilters LowerFilters . Right-click and select your system. 3. Clean Reinstall of Virtual Drivers
Residual files from older Mastercam versions or failed installations can cause conflicts. Remove Old Drivers: Device Manager
, find the entry with the exclamation mark (typically under "Universal Serial Bus controllers"), right-click, and select Uninstall device Manual Driver Update: For those using virtual license emulators like
, you may need updated 64-bit driver files that are compatible with the latest Windows updates. Run as Administrator: Ensure you run any driver installation command files (like install.cmd ) with full administrative privileges. 4. Check for External Conflicts Mastercam X7-2022 Virtual Usb Bus Error 39 - Google Groups
Important Note: Mastercam X7 is legacy software (circa 2013). Error 39 usually means the HASP/Sentinel driver (the virtual USB bus that hosts the network license) failed to start due to driver signature enforcement or a corrupted installation.
Once you fix the error, lock it down: