RSC-007: referenced resource could not be found
Epubcheck reports: ERROR(RSC-007): Referenced resource "images/cover.jpg"
could not be found in the EPUB. Something in the book points at a file that is not in
the archive.
What it means
An <img> whose src goes nowhere, a stylesheet
<link> to a CSS file that was never packed, a manifest entry for a file that
does not exist. In a reader this shows up as blank image boxes, unstyled chapters, or links
that do nothing. The validator flags each dead reference separately, so one missing file can
produce several of these.
Why it happens
- A file was renamed or moved during editing, and the references were not updated.
- The name matches except for case:
Cover.JPGon disk,cover.jpgin the reference. Paths inside an Epub are case sensitive even when your file system is not, which makes this one easy to miss on Windows. - The export or conversion tool simply forgot to pack the file.
How to fix it
For each reported reference, either restore the file at that exact path (case and all) or correct the reference to point at a file that exists. If the file is genuinely gone and you have no copy, remove the reference so readers stop trying to load it.
The checker lists every dead reference with the source file and line, and lets you view the surrounding markup without unpacking anything. Restoring a missing file or deleting a dead reference is a judgement call, so the fixer leaves that decision to you rather than guessing.
Find every dead reference