Troubleshoot status of NUM LOCK, SCROLL LOCK, F LOCK and CAPS LOCK keys

Depending on your keyboard model, you may have to turn F LOCK (F Lock Light on) to access system key commands if they are labeled on the front of the keys, such as INSERT, SCROLL LOCK, PRINT SCREEN and NUM LOCK.


You can download the latest software for your keyboard. To do so, visit the following Microsoft Web site:
When you press the NUM LOCK key, the CAPS LOCK key, or the F LOCK key, the associated status lights on the keyboard or on the wireless receiver turn on or off. The following is true for keyboards with a wireless receiver that contains the indicator lights:

• The "A" light on the receiver indicates that CAPS LOCK is turned on. CAPS LOCK toggles between uppercase and lowercase letters.
• The "1" light on the receiver indicates that NUM LOCK is turned on. NUM LOCK toggles the 10-key pad between numbers 0-9 and functions, such as HOME, END, PAGE UP, and PAGE DOWN.
• The "F" light on the receiver indicates that F LOCK (function lock) is turned on. F LOCK toggles between standard function keys (F1 - F12) and alternate commands, such as HELP, UNDO, NEW, AND PRINT.

You can also view the keyboard status lights by using the On Screen Display (OSD) option.

Make sure to download the latest IntelliPoint software from: To modify the on-screen display for a key, follow these steps:

1. Start the IntelliType software. (Use the shortcut on your desktop, or do a search for "Keyboard" from the Start menu.)
2. On the Key Settings tab, make sure that the correct Microsoft keyboard model name is selected. The keys that are available for customization depend on the model name that is selected.
3. To select a different keyboard, click Change, select the correct keyboard, and then click OK.
4. Double-click the key for which you want to change the on-screen display.
5. In the Reassign a Key wizard, clear the Displays (key name) status on the screen check box to disable the on-screen display, or select it so that a check mark is in the box to enable it, and then click Finish.

When you press the CAPS LOCK, SCROLL LOCK, or NUM LOCK key, the keyboard sends a scan code to the computer to tell it to turn the CAPS LOCK, SCROLL LOCK, or NUM LOCK state on or off. The computer maintains the CAPS LOCK, SCROLL LOCK, or NUM LOCK state and turns the appropriate indicator lights on or off. The following table shows the scan codes for the CAPS LOCK, NUM LOCK, and SCROLL LOCK keys: