Great tip from Chris Hahn :
To disable hot plug on a vSphere VM, add the following line to the VM configuration parameters : devices.hotplug false
Why would you want to do this?
With device hotplug enabled, a user that logs into a hardware version 7 VM will have the safely remove hardware icon appear in the taskbar. From here they can disconnect the NIC or SCSI controller, which will crash the VM in many cases. So a regular user logging into a Hosted Desktop (View, XenDesktop, or XenApp) VM could potentially open this and crash the virtual machine. With device hotplug disabled, these devices no longer appear in safely remove hardware.