My rear door does the same thing but I get a little resistance but it wont open. I would imagine it's something to do with the linkage at the latch which I can't get to because the same panel issue. Not motivated enough to risk the panel on a car I hardly drive. Will watch this thread and tackle mine when it warms up. Might be able to hook a coat hanger to the latch and pop it that way.
95 E34 530I V2.37
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Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy