These sliding bedroom closet doors needed repair because they kept coming off the track, and the only way to get them back on was to put the track wheel next to the track and bang them back in.
They looked like this, with a decorative face plate across the top.
This problem is a result of the fact that when the builders did the door installation on these doors, they set the decorative faceplate over the top of the doors under the molding so you can't take it off to fix the problem! The door hardware is such that the wheels must be angled in to the track and then allowed to hang back down. The permanent faceplate doesn't allow you to do this. So when the closet doors have come off the track and you bang the wheel back in you bend the track up and make the problem worse. The way to fix these types of sliding doors is to replace the track and make the faceplate removable as I have done, shown in the following pictures:
The old track (notice the dents):
A new track:
After the faceplate is removed, new wood is inserted to make the door jamb intact:
The new track is installed and the molding put back on:
The new faceplate is installed by being screwed into blocks installed underneath it:
Johnson Hardware 2200F Twin Wheel Sliding Bypass Door Hardware 72"