Followed the directions and worked great on my '04 E53 w/MKIV loving it....

BUT went to upgrade my buddy's '03 E39 540i Sport w/MKIV (SW 4 1/12) and crashed his Nav We managed to get the CD out with little problems and noted that the disk now had several scratches on it. Probabaly from it sliding in and out of my DVD and then his. I think that was the problem, but wondered if anyone else had issues trying to upgrade more than one MKIV.

Will burn another V31 tonight and try to re flash his Nav.

Question: Should I try and burn a lower version say V27 first, reflash then upgrade to V31 or just try a fresh CD with V31? THANKS