I didn't see anything about this issue here in the Getting Started forum, and thought other Wherigo newbies might benefit from what I learned.
If you're entering the unlock code that you received after completing a Wherigo cartridge, and no matter how carefully you copy it and double-check it, you keep getting the message:
Then count the number of characters in your unlock code.
Valid Wherigo unlock codes are 15 characters long. If you received an unlock code that was 16 charact