disk2vhd-hyper-v-boot-failure-with-gen2-server

https://www.theictguy.co.uk/disk2vhd-hyper-v-boot-failure-with-gen2-server/ 

Had an issue with a P2V of a Dell T330 with Windows Server 2012 R2 installed today. The Disk2VHD creation went fine and completed successfully. The VHDX files were moved to the new Hyper-V host and added to a Gen 2 VM, the problem occurred when booting.

Hyper-V unable to boot due to 99Mb RAW volume. disk2vhd Hyper-V boot failure.

• Add a new DVD Drive to the VM and mount the ISO for the Server OS you are trying to boot
• Change the boot order of the server to boot from DVD
• Turn on the server and when requested press any key to continue
• When the install has booted click Repair your computer
• Click Troubleshoot
• Click Command Prompt
• Type disk part
• Type list disk
• Type select disk 0 (or your main system disk)
• Type list volume and note which volume is showing as 99MB RAW
• Type select volume 3 (or whatever volume is your 99Mb RAW volume)
• Type assign letter L:
• Type FORMAT FS=FAT32 LABEL=”BOOT”

• Tyope exit ，exit diskpart

• Change to the new disk, type L:

• Type bootrec /fixboot to create the new boot record

• Type dir C: or dir D: to check windows folder

• Type bcdboot C:\Windows  /l en-us /s l: /f ALL to create a new BCD Store and to copy over the boot files from the Windows directory of the existing installation you are trying to boot.
• Type exit
• Click Continue to boot into your server as normal
• It is normal for the server to take longer to boot due to new hardware being detected and installed
• You may need to set the IP Address of the server on the NIC as it often installed a new Hyper-V NIC and doesn’t copy the original settings over.