http://blogs.msdn.com/virtual_pc_guy/archive/2008/06/11/hyper-v-script-compact-vhd.aspxContinuing on with my walk through the storage WMI API - here are some scripts for compacting VHDs with Hyper-V.&#160; Note that Hyper-V allows you to compact both differencing and dynamically expanding virtual hard disks. PowerShell: # Prompt for theen-USCommunityServer 2.1 SP1 (Build: 61025.2)http://blogs.msdn.com/virtual_pc_guy/archive/2008/06/11/hyper-v-script-compact-vhd.aspx#8593309Thu, 12 Jun 2008 18:55:23 GMT91d46819-8472-40ad-a661-2c78acb4018c:8593309Kieran<p>What is the purpose of compacting the VHDs though Ben?</p> http://blogs.msdn.com/virtual_pc_guy/archive/2008/06/11/hyper-v-script-compact-vhd.aspx#8649449Wed, 25 Jun 2008 01:31:59 GMT91d46819-8472-40ad-a661-2c78acb4018c:8649449aaron<p>Thanks for all the great tips, they've been exceptionally helpful.</p> <p>I have a server that is not hyper-v capable, but I would like to install the hyper-v tools to mount/defrag/compact vhds. &nbsp;Is there a way to do this?</p> http://blogs.msdn.com/virtual_pc_guy/archive/2008/06/11/hyper-v-script-compact-vhd.aspx#8657010Thu, 26 Jun 2008 17:53:59 GMT91d46819-8472-40ad-a661-2c78acb4018c:8657010Yossi Ran<p>I have just compacted a VHD</p> <p>Size before compaction: 9,524,588,032</p> <p>Size After &nbsp;compaction: 9,355,077,632</p> http://blogs.msdn.com/virtual_pc_guy/archive/2008/06/11/hyper-v-script-compact-vhd.aspx#8712204Wed, 09 Jul 2008 13:56:41 GMT91d46819-8472-40ad-a661-2c78acb4018c:8712204aya2work<p>Do I need to run pre-compactor tool (precompact.exe in VirtualServer) before compacting VHDs in Hyper-V?</p>