Microsoft today published a new System Center Virtual Machine Manager 2008 Knowledge Base article, that talks about an issue where when doing a P2V it may hang at ~70% and the resulting VM boots to a stop 7B:
"Attempting a SCVMM 2008 Physical to Virtual conversion (P2V) fails with Error (1730) at 70%. More specifically, the P2V conversion seems to hang at 70% in the VMM console. If you open the Hyper-v console on the host where the VM is being placed, you'll notice that the VM is in a reboot loop. If you connect to the VM, the reboot loop is actually a ST0P: 0x0000007b bugcheck," explains Microsoft in KB2007086 - A System Center Virtual Machine Manager 2008 P2V hangs at 70% - The new VM boots to a STOP:0x7B.
This problem can occur if a certain registry setting has been changed from the default value.
To resolve this issue, return the default value to the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Wdf01000\Group] = Base
Change the value above from "Base" to "WdfLoadGroup"