Hyper-V merging VHD and AVHD

[Jambo_C]

Hi,

 

I've got a 2008 R2 server running Hyper-V, one of the virtual servers has for some reason got a huge AVHD file despite me never taking any snapshots. The VHD file is 300GB and the AVHD is 580GB. I've only got 270GB of free space on the Hyper-V server. Am I correct in thinking that if I turn the virtual machine off it'll attempt to merge the files but will not be able to as I've not enough space? I want to allocate some more space to my virtual machine so could do with merging it, how can I do this? I have a couple of 3TB USB Hard drives, is it possible to copy the VHD and AVHD over to one of those, change the file path in Hyper-V and let it merge on the USB drive? If I do this though how do I shut the virtual machine down without it starting to merge?

 

Cheers.