Windows 7 install 'hanging' within Hyper-V

Recently I was required to create a Windows 7 VM within a Hyper-V environment (Server 2012 R2).  When creating the new Virtual Machine and installing Windows, I noticed that it would hang on 'Starting Windows':

There was nothing that could be done which would allow this VM to progress further than 'Starting Windows'.  Upon looking into the setup of the VM, I noticed it had been created as a 'Generation 2' machine.  Gen 2 Hyper-V machines are only support for Server 2012 or Windows 8 and above.  Because this was a Windows 7 VM, it wasn't supporting and not working.

To resolve this, you need to delete the VM, then go back into the Hyper-V Manager and make sure you select Gen 1 as your preferred VM Generation.