I tried to update my Humminbird 398ci SI from 6.67 to 6.73 through AS-PC connection cable (I don't trust SD
). But Humminbird PC 4.3.8 said that model is unknown and serial number is unknown, too. I can load tracks and waypoint, but can't update.
What can I do?
And, if the new version will be worse, where I can download 6.67 version?