If you have no leaks, the AC trick should work wonders. I don't even use the defroster button (windshield) because it's so loud. I use the 3 buttons on the left instead to direct the air where I want it. In this case, I'd suggest using at least the top two (windshield & face), turn the AC on, and put the fan on fairly high for a couple of minutes. Once the condensation clears up, just set the controls where you want them and leave the AC on and you should be all set...

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'08 335i Coupe - Barbera Red / Saddle Leather / Light Poplar Wood / 6spd Manual
Options: Sport, Premium, Cold Weather, Comfort Access, Active Steering (awesome!), Power Rear Shade, IPod Adapter, Navigation w/IDrive
Mods: M6 Wheels, Split Armrest, M-Steering Wheel, Euro Light Switch w/Rear Fog Lights, Short Shift Knob w/Matching E-Brake Handle, Clear Reflectors, CDV, Clear Bra

Retired:'04 X5 4.4i