Microsoft Windows XP Professional Corporate SP3

Builds on the strengths of Windows 2000 and NT, making it more powerful and stable than previous operating systems.
Wireless 802.1x Networking Support provides secured access, as well as performance improvements for wireless networks.
Runs hundreds of programs that didn't run on Windows 2000 and enables you to set up your system to run in compatibility mode
Encrypting File System provides the highest level of protection from hackers and data theft by transparently encrypting files with a randomly generated key.
User State Migration Tool can migrate a users data and application/operating settings from their old to their new desktop.
Windows Messenger lets you instantly communicate with friends and family all around the world from your computer, using text chat and even voice and video.
Learn to keep your computer and personal data more secure with Windows XP
Automatically keep your PC up-to-date with the latest security enhancements including the Windows Security Centre, Windows Firewall, and more to help protect it from viruses and worms that can spread through the Internet.
Quickly set up and connect all the computers, printers, devices, and an Internet connection in your Professional with the all new Network Setup Wizard. Sharing a computer with others has never been easier; quickly access your personal files and accounts without having to close applications or restart the computer.
If something goes wrong with your computer, you can easily remove and roll back any system or application changes without losing files and other valuable information.

Windows XP SP3 release: 2008-04-23