You can not install Navicore on a machine running OS2008...

Instead, use the "Map" program that was installed by default. Open it, then hit the arrow along the right side of the screen. A slide out menu will present you with a few options. One of the options will be "Enter License Code" or somesuch. Enter your old Navicore number (the one that starts with CD, do not add the CD BTW).

Unfortunately, since you deleted the Map program, you may have to re-flash OS2008.

There are quite a few threads on the subject or you can go to the "Wayfinder" site and drill down for the FAQ for Internet Tablets. Their FAQ answers all of these questions in greater detail.