Windows INSERT key anti-functionality accidentally triggers; how to stop it permanently?

How to Disable the Insert Key in Windows

Almost anyone who has used a wordprocessor has accidentally hit the Insert key and overwritten when they thought they were editing. This article describes a simple way to disable the Insert key on your keyboard.

Whenever you press a key, a windows message is created, which contains a key code that uniquely identifies the key pressed. Programmes (like Microsoft Word) look for keypress messages and take actions based on the key code in the message. By mapping the insert key press event to null, windows send a message containing null for the key code when the Insert key is pressed. Programmes receiving the message, therefore, do not perform the action associated with an insert key press event, freeing you from having to worry about overwriting things again.

1. Go to Start → Run → regedit
2. Go to HKLM\System\CurrentControlSet\Control\Keyboard Layout
3. Right-click on the right half of the screen and choose New → Binary Value
4. Name the new value Scancode Map
5. Enter 000000000000000002000000000052E000000000
6. Close regedit
7. Reboot.
8. Optional: you can take the Insert key off of your keyboard when done.

If you do this with Windows7 regedit, you have to enter the hex value in rows of 8 bytes, like this:

Value Data:
0000    00 00 00 00 00 00 00 00
0008    02 00 00 00 00 00 52 E0
0010    00 00 00 00

Source

Registry file (.reg) to apply the fix as described above

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Keyboard Layout]
"Scancode Map"=hex:00,00,00,00,00,00,00,00,02,00,00,00,00,00,52,e0,00,00,00,00

Put the above text into a file with a .reg extension (e.g.: disable-insert.reg), and double click.

The 0 key on the numeric keypad becomes insert when num lock is off.

When you type something in an MS-DOS application and go back to the middle of the phrase and press TAB, you switch to overwrite mode.