navigation program error

I have 03 IS300 with stock navigation. Someone showed me how to override and I was checking around menus. After I checked the Map selection, and pressed OK, I get the screen like this and stuck.

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Caution

Error: System unable to access the program.

Incorrect program disk.

Please insert proper disk.

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I reloaded the DVD but the screen remains. Anyone have any idea how to fix this?

Thank you in advance for your help.