The Nokia 2600 has a network feature that allows the phone's clock to automatically update itself based on the current time zone; however, if you do not have this feature selected, you'll need to manually set the clock yourself. Manually setting the clock is performed in the "Settings" menu. Getting to the menu and changing the time is simple and should only take you a minute or two.
Press the "Menu" button, and then scroll down and select "Settings." You can also push keypad button "4" to select "Settings."
Scroll down and select "Time Settings." You can also push button "4" from this menu to select "Time Settings."
Select "Clock and Date Settings." Choose either the "12" or "24" hour format, and then scroll down to the display clock.
Input the current time using your keypad. Push the soft key for "OK" when you are finished.
From the "Time and Date Settings" menu, check the box next to "Auto Update of Date and Time," if you wish for the Nokia to automatically update the time (based on the current time zone you are in, or daylight savings time).