# EPUBCheck OPF-031: guide link to missing file, how to fix it

Source: https://epubcc.com/epubcheck/opf-031/ (updated 2026-11-04)

EPUBCheck OPF-031 is an error message: “File listed in reference element in guide was not declared in OPF manifest: ….” A reference in the EPUB 2 guide element points to a file that is not in the manifest. The guide is a legacy list of key places (cover, table of contents, start), and its targets must be declared files.

- Official message (EPUBCheck 5.4.0): File listed in reference element in guide was not declared in OPF manifest: %1$s.
- Default severity: Error

## Typical causes

- A guide entry left after a file was removed or renamed.
- A wrong path or wrong case in the href of a reference element.
- A guide copied from another book.

## How to fix it

1. Find the reference element EPUBCheck points to in the guide.
2. Correct its href to a file declared in the manifest, or delete the entry.
3. In EPUB 3 the landmarks nav in the navigation document replaces the guide, so you can remove the guide if you do not target EPUB 2 reading systems.

## When it's not this

If the file is in the manifest but is not a content document, EPUBCheck reports OPF-032.

## Sources

- EPUB 3.3, §5.9.4 The guide element: https://www.w3.org/TR/epub-33/#sec-opf2-guide (read 2026-11-04)

Message text and severity: EPUBCheck (W3C, BSD-3-Clause). Explanation: EpubCC.