How to move Hyper-V guests from a crashed server to a new Hyper-V server?

If the original Hyper-V host computer was crashed, the best way should be restore the latest backup of Hyper-V.

However, if you don’t have a backup for the Hyper-V, here are the steps:

Scenario 1. No snapshots with the VM on the crashed Hyper-V computer

1 Create a new VM on the rebuilt Hyper-V server

2 Mount the existing VHDX to the VM.

Scenario 2.  There are snapshots with VM on the crashed Hyper-V computer

1 Merge the snapshots into the original VHDX first.

2 Repeat the steps in Scenario 1.