The Virtual USB Bus Error 39 in Mastercam (spanning versions from X7 to 2022) typically indicates that Windows cannot load the virtual device driver, often flagging it as corrupted or missing. This issue is frequently caused by modern Windows security features like Core Isolation or residual registry filters that block the driver from initializing correctly. Primary Fix: Disable Core Isolation (Memory Integrity) Most modern Windows 10 and 11 systems include a feature called "Memory Integrity" that prevents unsigned or older drivers from loading. Disabling this is often the most effective solution. Windows 10/11 Steps : Open the Start menu and type "Windows Security". Navigate to Device security on the left sidebar. Click on Core isolation details . Toggle the Memory integrity switch to Off . Restart your computer to apply the changes. Secondary Fix: Registry Editor (Upper and Lower Filters) If disabling Core Isolation doesn't work, specific registry entries known as "UpperFilters" or "LowerFilters" might be corrupting the USB stack. Press Win + R , type regedit , and hit Enter. Navigate to the following path: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{36FC9E60-C467-11CF-8056-444553540000} In the right-hand pane, look for UpperFilters or LowerFilters . Right-click them and select Delete . Restart your PC . Alternative Troubleshooting Steps If the error persists, consider these hardware and driver-specific actions:
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39 in Mastercam versions ranging from X7 to 2022 is primarily caused by Windows security features blocking unsigned or outdated virtual drivers.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 ). 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
Error 39 Virtual USB Bus Error in Mastercam X7 2022: A Comprehensive Fix Are you encountering the frustrating Error 39 Virtual USB Bus error while using Mastercam X7 2022? This issue can disrupt your workflow and hinder productivity. In this response, we will provide a step-by-step guide to resolve the Virtual USB Bus Error 39 in Mastercam X7 2022. What is Error 39 Virtual USB Bus Error? The Error 39 Virtual USB Bus error typically occurs when Mastercam X7 2022 fails to communicate with the USB dongle or license manager. This issue may arise due to a corrupted driver, outdated software, or a conflict with other system applications. Causes of Error 39 Virtual USB Bus Error:
Outdated or corrupted Virtual USB Bus driver Incompatible or outdated Mastercam X7 2022 software Conflicts with other system applications or drivers Issues with the USB dongle or license manager mastercam x72022 virtual usb bus error 39 fix
Step-by-Step Fix for Error 39 Virtual USB Bus Error:
Update Virtual USB Bus Driver:
Go to the Device Manager (Windows + X and select Device Manager) Expand the "Universal Serial Bus controllers" section Right-click on "Virtual USB Bus" and select "Update driver" Follow the prompts to search for and install the updated driver The Virtual USB Bus Error 39 in Mastercam
Update Mastercam X7 2022 Software:
Launch Mastercam X7 2022 and check for updates Install the latest service pack and updates
Disable and Re-enable Virtual USB Bus:
Go to the Device Manager (Windows + X and select Device Manager) Expand the "Universal Serial Bus controllers" section Right-click on "Virtual USB Bus" and select "Disable device" Wait for 10 seconds and re-enable the device
Uninstall and Reinstall Mastercam X7 2022: