I followed these directions and had no problems updating my nav unit.

Download file from: MEGAUPLOAD - The leading online storage and file delivery service

"Current version is 4-1/100

Updating your nav is highly recommended and easy to do.

Download the V31 or V32 image (both contain 4-1/100 Mk4 software)

Burn with a CD image buring program - I recommend ImgBurn (The Official ImgBurn Website).

Eject map CD
Turn ign on (but leave engine off)
Insert OS CD
Follow onscreen instructions - do NOT turn off ign during update process!
Remove CD when it is ejected and click OK to reboot
Voila!"

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Current: 2014 X3 35i, Titanium Silver, M Sport, Cold Weather, Premium, and Technology packages.

Previous BMW: 2006 X5 4.4, Stratus Grey, Nav, Sport & Cold Weather packages, BMW Running boards, Intravee II, Michelin Latitude Tour HP.