Hyper-V 2012 import VM hangs

Hi,

I'm trying to upgrade a Hyper-V 2008 R2 installation to Hyper-V 2012:

I've removed all of the snapshots, set the mac addresses to static and exported the existing machines to an external drive.

I've performed a clean install of Hyper-V 2012 and now I'm trying to import the machines back.

I've recreated the virtual switches as they were in the old configuration.

The issue is with importing the VMs back:

If I'm using the exports folder (via Resotre the virtual machine option), the import process hangs at 'Loading configuration'.

If I'm using the existing folder structure for the VM (via Register ...), the import process hangs at 'Performing import operation'.

Any ideas ?