I recently moved into a new place, and I want to remove the master bedroom closet doors. There are two sliding doors, connected to a track only at the top. The mechanism in question looks like this.
Friends on Facebook suggested loosening the screws (there’s one on each side of the door), but all that got me was a door that hangs down slightly and touches the floor. And I can’t get the screws back in. :smack:
In my experience, closet doors usually fall off pretty easily with some lifting and wiggling…but not these. Any ideas/suggestions?

Try tilting the door forward, then lifting up.
try lifting up and tilting the lower end to the rear to disengage.
First, physical description to make sure my observations about the picture do not overlook something.
The wheel sits in a groove in the track. The top edge of the track is smooth, no groove. The bracket has a rail or edge that runs along the bottom of the track when the screw is set properly. Undoing the screw lowers the bracket on the door and the door, while the wheel still sits in the track.
If so, I would lower the door to allow play of the bracket edge to the bottom of the track. Then rotate the door outward from the closet, with the wheel pivoting in the groove of the track and the top edge of the wheel sliding back into the closet. Take the door off as a unit. The length of those screws suggests that you may need to rotate outward slightly then extend the screws as you get more clearance between the door and the floor. It may be a two-person operation: one to hold the door while the other turns the screws.
Success!!
My problem was that I’d been doing everything from inside the closet: I finally stood in front of one of the doors and lifted up while pulling the bottom of the door towards me, and it came right off. Mocking me with the simplicity. 
Thanks, everyone!