I have 4.55a nav disk, my friend let me use his 4.73a nav. Disk to see if i thought it was worthwhile to upgrade. Not worth it to me. But can't get my 4.55a disk to work anymore. Can you zero out the internal memory in order to use the original disk. Thx

 

Hold down the Map/Guide, Menu, and Cancel buttons at the same time. In about five seconds, the secret decoder ring menu will come up. Select "Version" and go back to 4.55a.

LL

 

Ll
your solution was perfecto!!! Thx