Disk Management, a utility included in the Windows XP operating system, allows users to create, delete or format partitions on the hard drive. While it is a useful utility, it does not allow users to resize an already existing partition. To resize a Windows XP partition, you must use third-party software disk management software. Fortunately, resizing a partition is easy and requires only a few steps.
Log in to XP as an administrator. Download and install Acronis Disk Director, EASEUS Partition Master or 7tools Partition Manager (see Resources). Each of these programs will allow you to resize your hard drive's partitions.
Launch the software. Right-click the partition you wish to resize. Choose "Resize" or "Move/Resize" from the options.
Use the up and down arrows next to "Partition Size" to decrease or increase the size of the partition. Click "OK." Review your modifications in the left pane. Click the "Apply" or "Commit" button to permanently apply your changes.
EASEUS Partition Manager Home Edition will not work on Windows 7 64-bit. You must install EASEUS Partition Manager Professional instead.