Recouple Ranges resizes the range bar so that the beginning and end of the range matches the first and last keys in the track. This is useful to quickly realign the range and the keys after editing.
Ranges: Dope Sheet. Then, if you like, save your layout by right-clicking an empty area of the toolbar and choosing Save
Layout or Save Layout As.
Ranges: Dope Sheet.
(Position Ranges).
(Recouple Ranges).
3ds Max positions the range bars for the selected tracks to match up with the first and last keys in their track.
Position Ranges mode allows you to decouple the range bar from the animation keys. Recouple Ranges is a quick way to realign the range bars.