This happened to me on my 01 E53. Exact same thing. Ended up being on of the clips for the regulator, cable slipped out and bound up on the take-up pulley/roller.

Cut the cables, raise window and tape to hold in place. Replace window regulator and buy a couple of new clips for the window.

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2011 X5 35i Space Gray/Black Nevada Leather w Dark Bamboo Trim
Convenience Pkg/Running Boards/Cold Weather Pkg/Comfort Access
3rd Row Seating/20% Tint/Style 215 wrapped with Toyo Proxes ST II/ LUX v4

2001 X5 4.4i TiAG/Grey Leather-Retired
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