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Mastercam X72022 Virtual Usb Bus Error 39 Fix [portable] May 2026

To fix the Virtual USB Bus Error 39 in Mastercam (X7 through 2022 versions), you typically need to

address driver integrity issues caused by Windows security features or corrupted registry entries

The most common solution for modern Windows systems (10/11) is disabling Memory Integrity

, which often blocks virtual USB drivers used for licensing. Matsusada Precision 1. Disable Core Isolation (Memory Integrity)

Windows security can block the virtual driver from loading, resulting in Error 39. Windows Security (search for it in the Start menu). Device security Core isolation details Memory integrity

your computer and check the Device Manager to see if the error is gone. 2. Remove "UpperFilters" and "LowerFilters" in Registry

If disabling security doesn't work, corrupted registry values may be preventing the driver from loading. , and press Enter. Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\ Find the folder: 36FC9E60-C465-11CF-8056-444553540000 In the right pane, look for UpperFilters LowerFilters . Right-click and your computer. 3. Reinstall HASP Drivers

Corrupted drivers are a frequent cause. A clean reinstall is often necessary. How to Fix USB Error Code 39 In Windows 10/8/7 [Tutorial]

The "Virtual USB Bus Error 39" in Mastercam (typically appearing for older versions like X7 or when using virtual licensing/HASP tools on modern Windows) generally indicates that Windows has blocked a driver from loading because it doesn't meet security standards or has a corrupted registry entry .

The most effective fixes involve disabling Windows Core Isolation or cleaning the Registry. 1. Disable Memory Integrity (Most Likely Fix)

Modern Windows security features like Core Isolation (Memory Integrity) often block the older "MultiKey" or virtual USB bus drivers used by legacy software because they are not digitally signed to modern standards .

Action: Go to Windows Security > Device Security > Core Isolation details. Step: Toggle Memory Integrity to Off .

Restart: You must restart your PC for this to take effect. This is the primary reason why drivers that worked on Windows 7 fail on Windows 10/11 . 2. Remove Corrupted Registry Filters mastercam x72022 virtual usb bus error 39 fix

If Windows still cannot load the driver after disabling security features, "UpperFilters" or "LowerFilters" entries in the registry may be blocking the USB class .

Registry Path: Navigate to:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\36FC9E60-C465-11CF-8056-444553540000 .

Action: In the right-hand pane, look for UpperFilters or LowerFilters. If they exist, right-click and Delete them .

Warning: Back up your registry before making changes. After deleting these, restart your computer to force Windows to re-enumerate the USB stack . 3. Reinstall Virtual USB Bus Drivers

If the above steps fail, the driver file itself may be "Bad Image" or improperly registered. How to Fix USB Error Code 39 In Windows 10/8/7 [Tutorial]

After deleting the value, close the Registry Editor and restart the computer to see if the issue is resolved. YouTube·MDTechVideos

The Virtual USB Bus Error 39 in Mastercam versions ranging from X7 to 2022 is primarily caused by Windows security features blocking unsigned or outdated virtual drivers. Primary Fix: Disable Core Isolation

The most effective solution for Windows 10 and 11 users is disabling Memory Integrity, which often prevents the virtual USB bus driver from loading.

Open Windows Settings and navigate to Privacy & security > Windows Security. Select Device security and click on Core isolation details. Toggle the Memory integrity switch to Off. Restart your computer to apply the changes. Secondary Fix: Registry Filter Removal

If the error persists, corrupted registry "filters" may be the culprit. Press Win + R, type regedit, and hit Enter.

Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\.

Locate the folder corresponding to your USB device (often ends in 36FC9E60). To fix the Virtual USB Bus Error 39

In the right pane, right-click and Delete the values named UpperFilters and LowerFilters if they exist. Restart your PC. Additional Troubleshooting

Driver Reinstallation: Uninstall the "Virtual USB Bus" or "Sentinel/HASP" driver from Device Manager, then reinstall the latest version from the Mastercam website.

Check for Conflicts: Unplug other USB devices (like cell phones or 3D controllers) before starting Mastercam, as they can cause driver conflicts.

User Profile Corruption: In some corporate environments, a corrupt Windows User Profile has been known to cause this specific error; creating a new profile may resolve it. Mastercam X7-2022 Virtual Usb Bus Error 39 - Google Groups

A “USB Bus Error 39” in Mastercam X7 (or any software using a virtual USB dongle, like the 2022 version of the HASP/SafeNet emulator) usually means Windows cannot load the virtual device driver because its registry entries are corrupted or another driver is conflicting.

Here’s a focused review of the problem and the most reliable fix:

Phase 1: The "Clean" Uninstall

You cannot simply reinstall over the top; you must remove the USB filter driver completely.

  1. Uninstall Mastercam: Go to Control Panel > Programs and Features and uninstall Mastercam X7/2022.
  2. Uninstall the HASP Driver: In the same menu, look for "Sentinel Runtime Environment" or "HASP HL Device Driver" and uninstall it.
  3. Delete Remnant Files:
    • Navigate to C:\Program Files\Mastercam and delete the folder.
    • Navigate to C:\Windows\System32\drivers and look for files named hasp.sys, haspnt.sys, or vusb.sys. Delete them if present.

Fix 5: Reinstall CodeMeter + Mastercam Licensing Components

For Mastercam 2021–2022, Error 39 often stems from a broken CodeMeter installation.

Step-by-step reinstall:

  1. Uninstall all CodeMeter entries via Control Panel → Programs & Features.
  2. Download CodeMeter Runtime Cleaner from Wibu-Systems (official tool).
  3. Run the cleaner as Administrator → Select "Remove completely."
  4. Reboot.
  5. Download the latest CodeMeter Runtime Kit v7.60+ from the Wibu website.
  6. Install with antivirus fully disabled.
  7. Open Device Manager → Action → Scan for hardware changes.
  8. The Virtual USB Bus should reappear without error.

Fix 8: Use the Legacy "HASP Emulator" Workaround (For X7–X9 Only)

Some users on Mastercam X7–X9 bypass the virtual bus entirely by using a software emulator. Warning: This may violate your EULA. Use only if you own a physical HASP key that is malfunctioning.

Method:

  1. Uninstall all SafeNet/HASP drivers.
  2. Download HASP HL Driver 8.33 (last stable version for X9).
  3. Install the driver in compatibility mode (Windows 7).
  4. Use the HASP HELPER tool to disable the virtual bus and route through the physical parallel port emulation.

This is a niche fix but has saved many shops running legacy Mastercam on Windows 10/11. Uninstall Mastercam: Go to Control Panel > Programs

Introduction

For nearly a decade, users of Mastercam—from X7 to the 2022 release—have encountered a baffling licensing error:

"Windows cannot load the device driver for this hardware. The driver may be corrupted or missing. (Code 39)"

This appears in Device Manager under System devices as a broken entry named Virtual USB Bus. The error prevents the HASP (Hardware Against Software Piracy) or NetHASP license dongle from being recognized, rendering Mastercam unusable.

Despite appearing driver-related, Error 39 is rarely a true driver corruption issue. Instead, it stems from Windows driver signing enforcement, conflicting kernel drivers, or registry permission inheritance breaks—often triggered by Windows 10/11 feature updates, security patches, or third-party USB filtering software.

This feature provides a systematic, field-tested guide to diagnosing and eliminating Error 39 across Mastercam versions X7 through 2022, on Windows 10 and 11 (64-bit only).

What Exactly is Error 39?

Error 39 occurs when Windows cannot load a device driver that reports correct hardware IDs but fails during the start phase. Common causes include:

  1. Corrupted driver store (leftover files from previous Mastercam/CodeMeter installs)
  2. Digital signature enforcement (Windows 10/11 blocking older, unsigned virtual bus drivers)
  3. Conflicting virtual bus instances (e.g., from VMware, VirtualBox, or older SafeNet drivers)
  4. Registry debris from failed uninstalls of Mastercam X7–X9

For Mastercam, the "Virtual USB Bus" is typically part of the CodeMeter (for newer versions) or HASP SRM (for X7–X9) licensing infrastructure. Error 39 means Windows sees the device but refuses to let it start.

Most effective fix (step by step)

  1. Uninstall the broken driver

    • Open Device Manager → View → Show hidden devices.
    • Expand Universal Serial Bus controllers or SafeNet Inc. devices.
    • Right-click the device with error 39 → Uninstall device → check “Delete driver software”.

  2. Clean registry entries (use with care)

    • Press Win + R, type regedit.
    • Navigate to:
      HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\USB\
      Search for any key with “SafeNet” or “Virtual USB” and delete it.
    • Also check:
      HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\36FC9E60-C465-11CF-8056-444553540000
      Delete any UpperFilters or LowerFilters referring to the virtual bus.

  3. Reinstall the virtual USB driver manually

    • Download a clean copy of the emulator’s driver files (e.g., vusbbus.inf, vusbbus.sys).
    • In Device Manager → Action → Add legacy hardware → Install manually → Have disk → point to the .inf file.

  4. Disable driver signature enforcement (if on Windows 10/11)

    • Restart PC → press F8 or Shift+Restart → Troubleshoot → Advanced → Startup Settings → Disable driver signature enforcement.
    • Then reinstall the virtual USB driver.

  5. Prevent Windows from auto-updating the driver

    • Use gpedit.msc (Pro/Enterprise) or wushowhide.diagcab to block automatic driver updates for that specific device.