If you have an Internet connection, Windows XP can automatically synchronize your clock to keep it accurate. Here’s how:
1. Right-click your clock, and then click Adjust Date/Time.
2. Click the Internet Time tab. Click the Server down arrow, and then click time.nist.gov. Notice that Internet time synchronization is enabled by default.
3. Click Update Now. Windows XP contacts the Internet time server and sets your clock. Click OK.
Now, your PC is connected to the Internet time server.