LockDown Browser + Citrix / Parallels / VMware Conflict on Mac

Last updated 2026-05-02 · LDBypass Editorial

LDB on Mac blocks running VM hosts (Parallels, VMware, UTM, VirtualBox) via hypervisor flag detection, and blocks Citrix Workspace + remote-desktop tools as part of the screen-share blacklist. Quit each fully before launch - kernel extensions on VirtualBox specifically need a reboot to fully release.

The symptom

"Close these applications" dialog naming Citrix / Parallels / VMware / UTM / VirtualBox. LDB refuses to launch. Even after quitting the GUI, processes like prl_* or QEMUHelper remain in Activity Monitor.

Why it conflicts with LDB

Each VM host installs background processes + kernel extensions (older versions) + system services. The "quit GUI" action only closes the front-end; daemons persist. LDB scans for the daemons too, not just the GUI app.

The fix - pre-exam procedure

Parallels Desktop: Status menu icon → Quit Parallels Desktop entirely (not just the VM). Activity Monitor: search "prl" → force-quit any survivors (prl_naptd, prl_disp_service, prl_client_app).
VMware Fusion: Same - quit Fusion entirely. Force-quit VMware Fusion and VMware Fusion Helper processes.
UTM: Quit UTM. The QEMUHelper processes should exit on their own; if not, force-quit.
VirtualBox: Notoriously sticky kernel extensions. Quit VirtualBox GUI. If LDB still complains: open Activity Monitor → search "VBox" → force-quit. If still complaining, restart your Mac.
Citrix Workspace: Status menu icon → Quit. Activity Monitor: search "Citrix" → force-quit any Citrix Viewer / Citrix Receiver processes.
TeamViewer / AnyDesk / GoTo Resolve / LogMeIn / Chrome Remote Desktop: Same pattern - quit GUI + verify no helper processes remain.

Alternative configurations

If you actively use one of these for your daily work:

Parallels coherence mode: Switching out of Coherence is not enough - you need to quit Parallels entirely. There's no "exam-friendly" mode.
Citrix on a managed Mac: Disable Screen Sharing + Remote Management in System Settings → Sharing. ARDAgent quits when both are off.
VirtualBox kexts: If they refuse to release, reboot. Don't try to manually unload kexts - risk of system instability.

What NOT to do

Don't try to bypass the conflict mid-exam - LDB's blacklist scan happens before exam launch and re-runs at intervals.
Don't restart the conflicting app DURING the exam - LDB will detect the new process and may flag.
Don't leave the conflicting app paused/disabled long-term outside exam windows; that's overkill for non-LDB use.

Frequently asked questions

Will LDB detect Parallels even if no VM is running?

Yes - Respondus's detection looks at the host app + kernel daemons, not active VM state. Parallels with no VM running is still flagged.

Can I take the exam inside a Parallels Windows VM?

No. Respondus explicitly detects and blocks virtualised macOS or Windows. <a href="https://support.respondus.com/hc/en-us/articles/4409604116123-I-receive-a-warning-The-browser-cant-be-used-in-virtual-machine-software-such-as-Virtual-PC-VMWare-and-Parallels" rel="noopener">Vendor confirms this</a>. Use native macOS.

What about UTM running Linux for development purposes?

UTM is detected even if running Linux (not macOS or Windows). The detection is at the hypervisor level. Quit UTM before exams.