Warning
The size of the available shrink space can be restricted by the amount of space currently allocated to on the hard drive for the virtual memory page file, System Protection maximum storage space size, and hibernation files. The location of the files on the hard drive plays a big part here because these files are marked as unmovable, and Disk Management is unable to relocate them. As such, if these unmovable files are located in the middle of the total amount of free space on the disk, then only the amount of free space on the other side (to the right) of these files will actually be available for the new partition. This will result in you showing that you have x amount of free space, but not being able to use it for your partition. The only way around this is to use a 3rd party hard drive partition management program, or setup the partition when installing Vista.
