The guest vm needs to be shutdown.
Remove any superfluous hardware such as cdrom drives and floppy drives and usb.
In the Inventory panel, right click the virtual machine, Settings, Options, Advanced, General
Click Configuration Parameters button
Add the following lines to the guests vmx file…
isolation.tools.diskWiper.disable=true
isolation.tools.diskShrink.disable=true
isolation.device.connectable.disable=true
isolation.device.edit.disable=true
log.rotateSize=1000000
log.keepOld=10
remoteDisplay.maxConnections=1