Booting a virtual machine under Hyper-V may result in the following error:
Info: There isn’t enough memory available to create a ramdisk device.
Windows failed to start. A recent hardware or software change might be the cause.
In my case, this message appeared under Windows Server 2012 R2 Hyper-V, while installing Windows Server 2016. But it may also pop up installing Windows 10 under Windows Server 2016 Hyper-V.
The VM is configured with Dynamic Memory enabled. I set the Startup RAM to 512 MB, the Minimum RAM to 512 MB and the Maximum RAM to 4096 MB. This is a problematic configuration, because Windows Boot Manager cannot make use of this dynamic RAM. It will therefor only get 512MB assigned to the VM in this stage, which is too low.
Setting the Startup RAM to 1024 MB will fix the problem. The minimum RAM can still be configured at 512 MB. If memory consumption in the OS decreases, the VM returns the unused memory.
The increase of the startup memory is probably also a solution for VMWare vSphere oriented environments.