Tips for compacting virtual hard disks

A couple of weeks ago Guoqiang Wu posted an article on compacting virtual hard disks (  The main issue he addresses is that in order to efficiently compact a virtual hard disk – you need to defragment both the files and free space on the virtual hard disk before running the Virtual Disk Pre-compactor.  The problem here is that the built in Windows defragmentation tool does not defragment free space.

Guoqiang recommends this free defragmentation tool: which I have used in the past with much success.  However these days I prefer to use DisKeeper ( as I find that this is a much more user friendly solution and find that I always get smaller virtual hard disks as a result.