epub and calibre
I am very new to epubs and trying to learn how it works. I was accessed to examine a clients epub that would not validate and it shows that it was created in calibre and with word. I was trying to learn the structure but I am getting an error and I dont know how to solve it. The message I am getting is as followed:
This resource is present in the OPF <Manifest>, but its not reachable (it's unused).
What does this exactly mean and how do I fix it?? It lists this error message with each jpg.