I have an HP MicroServer that I use for dev/test. I've successfully installed Windows 2019 Server Standard on it (a dozen times now!) - and everything works great until I add the Hyper-V role. (This server was previously running Windows Server 2016 with Hyper-V with no issues.)
Once I add the Hyper-V role, and reboot, the thing just goes into a boot loop. When the boot loop happens, there is no BSOD, just a reboot every time. I've tried to boot into "safe mode" and remove the role, but even after doing that, it just continues in a reboot loop. After a few failed boots, it'll kick into the automatic repair screen, and that appears to be no help.
What is the best way to troubleshoot this and get Hyper-V installed? I've tried adding the role via the server manager, powershell, the new Windows Admin Center - and have the same results every time. Am I missing some sort of prerequisite for Hyper-V that the installer isn't adding automatically?