Just a thought...Do you have the latest supported BIOS for your system.An updated Hardened FreeBSD 11.2 is used now and may require a later BIOS?Possibly worth checking any other firmware for storage controllers etc
What version of Hyper-V are you running? I have installed OPNSense on 2012 R2, 2016, and 2019. That all said, I did have the issue when installing 19.1 on Hyper-V 2019 where it would get stuck at selecting the install destination, but the CTRL-C would get it through that.A thought would be to add an IDE controller and attach a HDD to that to see if that allows it through. I have other non-OPNSense BSD versions like the IDE controller better than the SCSI. Lastly, I can build an OPNSense VM on Hyper-V, export it, and give you a link to see if it is just the install or OPNSense as a whole on your particular setup.
I apologize for the delay, ended up in meetings all day yesterday. Here is the link to get it:https://www.dropbox.com/s/xasw9wz8vmdv7yf/OPNSense_19_1_4.zip?dl=0It will expire in 15 days. I did the following:Gen 2 VM (Secure Boot Off)2x vCPU3GB of RAM32GB of HDD (SCSI 0:0)2x vNICInstalled 19.1.4 (image I had laying around) using Guided Install method and GPT/UEFI for disk. Default login.I did test it by putting an IP on the LAN interface and hooking it up to my test network. It passed traffic and worked. I then reset it all to factory defaults using the console menu. Hopefully that helps!
Pfsense is using FreeBSD 11.2, whereas OPNsense is using 'Hardened FreeBSD' 11.2 https://hardenedbsd.org/I believe some components are removed from a standard FreeBSD kernel when creating a Hardened BSD build in an attempt to reduce the possible attack surface among other things.If you're on the latest supported BIOS and firmware then it might be a request to the Hardened BSD team to see what is going on.OPNsense and Hardened BSD have a pretty close relationship from what I understand, so hopefully one of their team can help with getting you past this boot error.Edit: You could try downloading HBSD 11.2 and booting that up in Hyper-V 2019. See if it fails at the same point. This would point to either OPNsense or HBSD as being the issue.