I have yet to get round to fixing the rear offside window on my 2008 HSE. It doesn't raise or lower all the way on either front or rear buttons, rather it goes a couple of inches and stops. Buy it does actually close and open, so it hasn't been a priority.

I thought I would have a go at it a couple of weeks ago prior to a trip across the Channel, and it worked. Perfectly, every time.

Now it's started raining it's back to the way it was, just an inch or so each time.

Apart from this being interesting, does it tell me anything about what's going wrong?

Water in the channels making the glass stick? Maybe let them dry out and spray some silicone lubricant into the channels.