Had the exact same problem after my upgrade from 11.10 to 12.04. This time the file I had to edit to make my MX5500 to work is /lib/udev/rules.d/97-bluetooth-hid2hci.rules
Had the exact same problem after my upgrade from 11.10 to 12.04. This time the file I had to edit to make my MX5500 to work is /lib/udev/ rules.d/ 97-bluetooth- hid2hci. rules