our sliding glass door has dropped at one end.to close the door we have to push the top corner of the door to close and lock the door.is this a roller problem?i have looked at how to remove the door but i cannot figure it out,this is a very old door.
You usually have to slide them all the way open and then lift the door upwards and pull out at the bottom. Sometimes there's a stop-block that you have to remove to slide it open far enough.

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door repairs