Using HotKeySet

Hello All,

I am trying to use Hotkeyset to detect when a user presses ALT + SHIFT + Backspace + DEL

When this key combination is pressed simultaneously I will call my function. Here is what I have so far:

;This calls my function as soon as ALT + SHIFT + DEL is pressed (doesn't wait for backspace)
HotKeySet("!+{DEL}{BS}", "Escape")


Can anyone tell me what i am doing wrong?