If your sliding door does not roll smoothly along the bottom of the door, tightening or loosening the adjusting screws at the bottom metal frame of the door may help the rollers perform better. If the door is still hard to open, try cleaning the bottom track where the door is getting stuck. You can remove any dirt and debris that may be causing the issue. If neither of these tricks improves the function of your sliding glass door, replacing the rollers may be the next step and involves removing the door from its track. A professional may be engaged at this level.