Adjust swinging glass shower doors by loosening the screws, moving the door in the U-shaped channel and then tightening the screws again. Most swinging doors have adjustments on both sides so owners can make several adjustments to fit irregularities in the walls.
If installed properly, sliding glass shower doors rarely require adjustment to work correctly. However, the rollers at the top and bottom of the door can stick or wear. Remove the door from the rack to replace worn rollers so that they do not cause excessive wear or permanent damage. Sliding glass doors with such damage often require replacement.