I recently had the passenger front side window regulator replaced. On completion the ecu had been re booted. Unfortunately now the same wing mirror folds the opposite way to the way it should. Any idea what is gone wrong.

I'm not sure I understand the situation, regarding the "opposite" meaning ... instead of closing the wing mirror (by remote I suppose), it opens? Mechanically, it can't go much further than the already open position if it is opened (unless the wing mirror center post is broken, but then you'd easily tilt the wing mirror every which way with your hand).

Is it a new or used part and who fitted it?

 

Sounds like it's not the right one for your vehicle, where are you based?