Changes

In order to accommodate CentOS on a disk drive that already contains a Windows installation the first step involves shrinking the Windows partition to make some room. If you are running Windows Vista, Windows 7 or Windows Server 2008 the recommended course of action is to use the Windows Disk Management interface to reduce the size of the partition before attempting to install CentOS. You can generally access this by right clicking on the Computer icon and selecting Manage from the popup menu. Within the Computer Management interface, select Disk Management to display a graphical representation of the disk drives in your system:

Right click on the partition you wish to reduce and select Shrink Volume. The tool will calculate the maximum amount by which the volume can be shrunk without data loss (a process that can take several minutes depending on the overall size of the partition). Once this analysis is complete, a dialog similar to the one in the following figure will appear:

Enter into the Total size after shrink in MB field the new target size for the partition and click on Shrink to proceed. Once the resizing operation is complete, reboot using the CentOS installation media (as outlined in Installing CentOS on a Clean Disk Drive) and proceed with the installation. When prompted to decide on where CentOS is to be installed be sure to select the Use free space on selected drives and create default layout option.