Only if you're trying to update the Nav OS on the MKIII, and only when it's updating to a certain range of OS versions (but I totally forget which versions require a key CD by now).
Originally Posted by chrisn7
Doesn't the MkIII need a software key as well?
2000 740iS. MKIV, 16x9, DDEs controlled by Euro fog light switch, reversed steptronic +/- pattern, paddle shifters, clear corners, Basslink, Alpine DVD changer with stereo audio, TV tuner, gauge rings, ///M pedals, backup camera with 'on demand' switch, quad brake lights, Dinan engine & tranny software, windows/sunroof close via remote.
2003 540iS. MKIV, 16x9, PDC, CWP, TV tuner, backup camera with 'on demand' switch, paddle shifters, windows/sunroof close via remote, iPod video & audio.