VirtualBox disk deframenting

Assuming an windows image, first run defragger:

http://www.mydefrag.com/

Zero freespace w/ sdelete available from http://technet.microsoft.com/en-us/sysinternals/bb897443.aspx

sdelete -c

From command/terminal:

VBoxManage modifyhd diskname.vdi –compact

Thanks: http://www.processworks.de/blog/2010/07/how-to-shrink-a-virtualbox-vdi-disk-image-to-the-required-size/