FineDrive 400 software upgrade problem

Question

Hi,I've downloaded the instruction, the install data andthe map data and followed the instruction to intallthe software and map upgrade. However, I kept gettingthe map incorrect version dialog pop-up. I don't knowwhat else to do. Do you know how or have theinstruction to go back to my previous version beforeperforming the upgrade? I've backed up my SD cardbefore the upgrade. Thanks