HOW TO: Change a GUID Partition Table Disk into a Master Boot Record Disk in Windows XP

This step-by-step article describes how to change a GUID partition table (GPT) disk into a master boot record (MBR) disk (64-bit only).

Using the Windows Interface

1. Right-click My Computer and click Manage.
2. Click Disk Management.
3. Right-click the GPT disk you want to change into an MBR disk, and then click Convert to MBR disk.

Using a Command Line

1. At a command prompt, type: diskpart, and then press ENTER.
2. At the diskpart prompt, type: list disk, and then press ENTER.
3. Record the disk number of the disk that you want to convert to an MBR disk.
4. At the diskpart prompt, type: select disk n, and then press ENTER.
5. At the diskpart prompt, type: convert mbr, and then press ENTER.

You must be logged on as an administrator or a member of the Administrators group to complete this procedure. If your computer is connected to a network, the network policy settings may prevent you from completing this procedure.

On Itanium-based computers, you can change a disk from GPT to MBR, provided that the disk is empty.