Obviously, you do not want to work on a laptop with the power turned on and plugged into a wall outlet. There are eight total screws that you will need to remove. These screws do not actually fall out.
You just have to loosen them enough so that you can take off the bottom cover. On one side of this Lenovo Thinkpad L450 laptop computer system is a blank piece of plastic that fits into an empty slot. You must take this out in order to remove this cover.
In order to avoid scratching up this laptop computer case, you will want to use a computer pick made out of plastic. I supposed you could use a guitar pick as well. You do not want to use metal objects, which can easily scratch up this plastic case.
You are going to use this plastic device to loosen the bottom cover from the rest of the case. Once the bottom cover is loose then you will be able to pull the cover off. There is one screw holding down this hard drive that you need to remove.
Now you can just pull the serial advanced technology attachment hard drive from that slot and replace it. Then you just tighten down the one screw holding the hard drive in place. You will want to press in the bottom cover on all four sides.
It should snap back in, but you still need to tighten those eight screws. Congratulations, as you have just successfully changed that laptop hard drive in a Lenovo Thinkpad L450 laptop computer system. You will want to make sure the bottom cover snapped in tightly and that none of those screws are loose.