If you have a constant Internet connection that a DSL or cable modem gives you, your computer will automatically update the time by connecting to a time server on the Internet.
The automatic time updating may not occur with a dial-up modem connection, but you can manually update the time once you are connected.
Double-click the time display on the right side of the Taskbar to open the Date and Time Properties dialog box.
Click the Internet Time tab and place a checkmark next to Automatically synchronize with an Internet time server.
Click Update Now. Windows will contact the time server and set the correct time on your computer. Click OK to close the dialog box.