In some instances the Administrator needs to reset the virtual firewall to factory default.
Factory Default the SonicWall virtual firewall
1. Connect to console from ESXi web interface, by clicking on Console and select "Open browser console"

2. Console window pops up:

3. Press Ctrl+s, release, then press spacebar to switch to GUI console:

4. Select "Boot with Factory Default Settings", and confirm:

5. After reboot, the virtual firewall should be in factory default