05 Odyssey NAVI code

I just purchased an 05 Honda Odyssey. While checking out all the gadgets, I ran down the battery. When we jumped it, the navigation system started asking for a 4 digit code. The card that was in the glove box that says NAVI code is 5 digits. I tried many 4 digit variations of this code and parts of other codes I could find, and as you may have guessed by now, I am no longer prompted with a code screen. I fear I have locked myself out. How can I get my system back and how can I get my 4 digit code?

Please help.

Call Honda, who will probably help, or suggest a visit to a dealer. Let dealer now that Honda suggested them to help, and don’t expect to pay a cent.