Now I will show you how to deal with Compaq CQ Series CQ45 (Black) Keyboard problem:
Carefully remove another key by prying it off gently with a small flathead screwdriver.
Examine the configuration of the key you've just removed. If a key has come off your Compaq CQ Series CQ45 (Black) Keyboard , you may have difficulty figuring out how to put it back on because the configuration of the key retainer is a bit complicated and will be somewhat unique to your machine. The key retainer is the white plastic piece that goes between the key itself and the hardware that the key engages.
Place the key retainer from the first broken key back in place according to how the retainer for the key you've just removed is situated.