Windows allows you to control appearance of your taskbar. Among other things it allows you to disable the taskbar clock. World Clock observes this system setting. In other words, when taskbar clock is turned off, World Clock will not show any clocks in taskbar. To see clocks in taskbar you need to enable the system clock back.
In Windows Vista: 1. Start with right-clicking on a free area of taskbar and then selecting Properties. Then click on the "Notifications Area" tab.
2. Then, tick the "Clock" option in Taskbar and Start Menu Properties and click OK.
In Windows 7: 1. In taskbar notification area click on the "Show Hidden Icons" small button with a triangle on it.
2. You should see something like this:
3. Click the "Customize..." link below icons.
4. On the bottom of "Notification Area Icons" screen click the "Turn system icons on or off" link.
5. On the "System Icons" screen turn the system clock on.