See if your Windows XP-based PC can run Windows Vista. Just download, install, and run the Windows Vista Upgrade Advisor.

Find out how to troubleshoot common (and not-so-common) problems using Windows XP.

Follow these quick guidelines to maintain your computer and keep it running smoothly.

The newest version of Windows is now available! Choose the edition designed for the way you use your PC, from home to business.

Download Windows Defender for Windows XP for free and help protect your computer against spyware.

Download the latest release of Windows Media Player and experience MTV's URGE music service.

Upgrade your browser with confidence. Get tabbed browsing, better printing, easier searches, and improved security.

See how to update your computer for recent changes in the U.S.

From security to digital photography, from games to networking, learn how to use the features and technology that come with Windows XP.

Find troubleshooting tips, guided help, and downloads for Windows XP.

Visit the Expert Zone community for tips and advice from friendly experts and to connect with Windows XP users like you.

Get advice, products, tools, and information tailored to your business in the Microsoft Small Business Center.

Windows Vista is available in two editions for business: Windows Vista Business and Windows Vista Enterprise. See which is right for you.

Get how-to articles, troubleshooting advice, and other resources for IT professionals on TechNet.

Download this tool to assess your existing PCs' readiness for Windows Vista network-wide.

For Windows Vista knowledge, there's no better place for IT pros to start than TechNet.

Get guidance for how to optimally deploy Windows Vista and the 2007 Office system.

Find technical articles, code samples, and more for Windows XP.

Get the information you need to develop applications for Windows Vista at this MSDN Developer Center.