If you are running Windows 8, hit the Windows key and L at the same time. What do you see? It should be the lock screen complete with the date, time and weather. What format do the date and time take? It’s almost certainly the same as the clock in your taskbar – if you have opted to use 24 hour clock format, it will be used in both places. But this doesn’t have to be the case; customization is possible.

You might think that a quick visit to the Control Panel is all that’s needed to change the appearance of the Lock Screen time and date. To some extent this is true. The Region applet can be used to configure formatting, but this is a system-wide setting. By editing the registry it is possible to use different formatting on the lock screen.

Fire up the Registry editor and navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\ SystemProtectedUserData\S-1-5-21-[unique ID]\ AnyoneRead\LocaleInfo.

You will need to make this key editable, so right click LocaleInfo, select Permissions and make sure both of the Allow boxes are ticked before clicking OK.

There are several settings to the right that can be adjusted, but it is the TimeFormat key that is of particular interest. As with the time format in the Region Control Panel, you can use basic syntax to adjust the appearance of the time.

HH:mm uses 24-hour format with a leading zero, H:mm without it, hh:mm is used for 12-hour time with the zero, and h:mm to drop it. Add tt to include AM and PM indicators. Editing this setting via the registry enables you to choose to display time in different format to the taskbar clock.

You can also get creative and add ASCII art to your clock if you want to get a somewhat different look for your lock screen.

The changes take effect immediately – there’s no need to restart Windows.