First, double-check that you entered the complete code (it should be 16 digits), without adding any spaces.
Tip: Our codes do not include the number ‘0’ or the letter ‘O’
If you have a book, make sure your code can be used on cambridgeone.org, you'll find it below the activation code.
If problems continue, contact us with the following:
- A photo of the activation code printed on the book or card
- A photo of the ISBN printed on the book (you can find this number on the back cover, next to the bar code. It will start with 978)
- Your username or email address.