How do you remove the front cover from compaq presario 5000Z it only has one side that unscrews I found some plastic tabs three on the inside but still cannot remove it :(

Generally speaking any case with a plastic front that is kept on by tabs also has tabs not only on the sides but on top and bottom. 90% of the time you have to remove at least some components to get to the other tabs or even to be able to see them. Also sometimes they will hide the tabs on top with the top cover to the PC(check for screw's or tabs to undo). Slide it off and see if you can see more tabs.

Try remopving the panel on the motherboard side and seeing if there is some screws there holding it in