PXE Boot a Virtual Machine In Hyper-V 2008 R2

PXE boot is not available in Hyper-V 2008 R2 when using a Synthetic Network Adapter.  In order to PXE boot a virtual machine (VM), you need to turn off the VM and add a Legacy Network Adapter.  If the VM is an existing machine with a bootable hard disk, you’ll also need to change the boot order, so PXE Boot is above IDE Hard Drive.