The HDD caddy for Asus N56 is easily to install the Asus N56 laptop. However sometimes it is difficult to take out the HDD Caddy, it seems to get stuck halfway. Thanks to a tip of Gerwin we have the following solution.
Please take out the caddy out as far as possible.
Take out the HDD from the caddy.
Now move your fingers inside the caddy.
You can feel there is a small metal plate blocking the caddy from moving out.
Press your fingers against this metal plate and take out the caddy.