Why does our car always have misty windows?

My wife has a 2013 Nissan Micra and finds in certain conditions that the windows severely mist up, even on a dry day. We have checked there are no damp carpets, no damp patches under the spare wheel nor...

How do I stop water leaks in my car through the air vents?

I have had problems with water getting into the front of my car through the air vents if the drain in the air box gets blocked, usually by leaves. How can I stop this?