It failed for me 8 or so times on my work laptop. I already had ActiveSync installed and some modem drivers installed for the 760, not sure if they were the same version or not.

I finally went to a fresh desktop (XP), installed ActiveSync 4.5 then ran the updater.. the updater added the modem drivers for me. The update still failed the first time at the phone part, but the 2nd time it worked no problem.

I then took my buddy's 760 this am to that same machine and ran the upgrade. Failed the first time on the phone part and worked the 2nd time. So weird.