Well, there is a solution... but it's not going to be fun in freezing temps. Maybe not even possible if the doors are frozen shut. At autozone (or whatever the Canadian equivalent if no AZ) you can find door poppers. It's basically an inflatable bag, a wedge, and a couple of long poles with a hook. You'll have to pry open the door with the wedge enough to slide the uninflated bag in. Then inflate the bag. This should crack the door open enough to use the hook to pull the door lock handle from the inside. We used to use them when the mechanics would lock keys in the cars at the shop.

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2005 X5 4.4i Build 04/05 Maintenance/Build Log
Nav, Pano, Sport (Purchased 06/14 w/ 109,000 miles) (Sold 8/15 w/121,000 miles)

2006 X5 4.8is Build 11/05 Maintenance/Build Log
Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

2010 X5 35d Build 02/10
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