An Invalid Subscription notice could mean multiple things:
-The book you purchased is the wrong book for your class. You will need to purchase the correct book. Many of our books have similar or identical titles. Please verify that the ISBN and author of the book you purchased is correct for your course.
-Your Product Key has expired. Product Keys are valid for 6 months, you may need to purchase a new Product Key (available with the purchase of eBook+ or Textbook+ Loose Leaf Bundle formats).
-If you are retaking a course please verify the Section Code you have entered for your class. You may need to obtain the correct Section Code from your instructor.
-You have joined your class but have not redeemed your Product Key yet. The Product Key can be found in the back of your Loose Leaf textbook if you purchased the Textbook+ Loose Leaf Bundle, or in your e-mail if you purchased the eBook+ from our online student store.
If you still need further assistance, e-mail firstname.lastname@example.org.