The code does not work with the instructions... or the publisher website says "invalid code" or "code is too long".

First, please verify that the code is entered exactly as it appears. Make sure to enter the dashes when registering your access code. Each access code can only be redeemed once when you register. The access code is only needed to register. It is not needed to sign in. You will set up a Sign-in name and password when you register. The code is case-sensitive. Also, verify that the "0" and "O" or "I" and "l" are entered as the right letter or number. If you still have trouble please submit a support ticket on shelfit.com, and one of our agents will assist you in resolving this inquiry.