Restoring the deleted or missing Clock on Task bar of Windows XP

1) Go to "Start" button, (Start button is located at the bottom-left of your Windows screen)
2) Right click on the "Start" button, you will be displayed with options like: Open, Explore, Search, Properties.
3) Select Properties, you will be displayed with a window named "Taskbar and Start Menu Properties".
4) Click "Taskbar" tab that is located adjacent to "Start Menu" tab, (Both tabs are located right below the "Taskbar and Start Menu Properties").
5) Once you click on Taskbar tab, the put a check mark in the square box for "Show the clock".
6) Click on "Apply" and then finally click on "Ok" button.

By following the above steps you can restore the Clock on your Taskbar.