|  | Upgrading to Windows XP Professional Upgrading Computers Running Windows 2000, or Windows NT Workstation 4.0 SP 5
The upgrade process for client computers running Windows 2000, or Windows NT Workstation 4.0 SP 6 is similar to the upgrade process for client computers running Windows 98. To upgrade clients running Windows NT Workstation 4.0, perform the following tasks: Start the computer from the product CD. Select the Upgrade to Windows XP Professional (Recommended) check box, and then click Next. Read and accept the licensing agreement. If you are installing the system onto an existing FAT partition, specify whether you want to convert the partition to NTFS. The files are copied, the computer restarts, and the upgrade finishes without further user intervention.
| Important: When upgrading from Windows 2000 to Windows XP Professional, the upgrade cannot be reversed. Therefore, after upgrading to Windows XP Professional, the only way to return to Windows 2000 is by reinstalling the product.