EPUB FixerKDP upload error scanner

EPUB error guide

Referenced resource could not be found in the EPUB

How to trace the exact 'referenced resource could not be found' EPUB message back to the broken internal path before another KDP or Kindle Previewer retry.

1. Example report output

What the scan report should show.

A useful report should name both sides of the broken reference: where the pointer lives and which packaged file it tried to reach.

Source file

OEBPS/Text/chapter1.xhtml

Broken target

../Images/Cover.jpg

Closest match

OEBPS/images/cover.jpg

Decision

Safe fix only if this is the single matching packaged image.

If no matching file exists, restore the image from the source project instead of generating a placeholder.

2. Next step

Use the report to choose scan, manual check, or source repair.

This error is only actionable after you know whether the target file exists somewhere in the EPUB.

Upload scan

Use this when you only have the validator message.

The scanner can locate the XHTML, CSS, nav, NCX, or OPF file that contains the broken pointer.

Manual check

Use this when several files look similar.

Compare the actual chapter, image, or stylesheet context before choosing one target.

Formatter handoff

Use this when the file is truly missing.

Send the formatter the validator message, source file, missing target, and original EPUB export project.

3. Concrete path example

A real missing-resource path usually looks like this.

The important detail is the internal EPUB path, not the folder path on your computer.

Source: OEBPS/Text/chapter1.xhtml
Broken: ../Images/Cover.jpg
Found:  OEBPS/images/cover.jpg
Fix:    update the XHTML reference only if this match is unique

If the package has no cover image at all, the next step is source repair, not automatic replacement.

Quick decision

Decide whether this is a path fix or a missing-file problem.

Use the exact internal path from the validator. The right next step changes depending on whether the target exists somewhere in the EPUB.

Scan first

You only have the KDP or Previewer message.

Upload the EPUB so the report can show the source file and missing target instead of making you search every XHTML, CSS, nav, NCX, and OPF file by hand.

Safe fix

The same file exists with a clear name mismatch.

A single case, folder, space, or encoding mismatch is usually a path-alignment fix, then the EPUB should be validated again.

Stop

The target file is not in the package.

Restore the missing image, stylesheet, chapter, nav, or NCX file from the source project. Do not create placeholder content just to pass validation.

Start here

Find the missing target before you rename or delete anything.

This message is about a path inside the EPUB, not a file on your desktop. Copy the validator wording, the file that contains the reference if it is shown, and the missing target path exactly as written.

What it means

A chapter, stylesheet, navigation file, NCX file, OPF entry, or image reference is asking for a file name the EPUB package cannot resolve.

Can it be fixed automatically?

EPUB Fixer can treat this as safe only when the missing target has one clear match, such as Cover.jpg versus cover.jpg, an encoded-space mismatch, or a resource that exists and only needs a manifest or reference alignment.

What to check next

Copy the exact missing target path from the message, including folder name, capitalization, spaces, URL-encoded characters, and anything after a # symbol.

What not to assume

If the target image, CSS, XHTML, nav, or NCX file is truly absent, the safe fix is to restore it from the source project or remove the broken reference with intent. The tool should not create a blank image, invent a stylesheet, or guess which chapter the author meant.

Common situations

Match the missing resource to the file that points at it.

The same message can come from several places inside the EPUB. Start with the source type before choosing a repair.

A chapter points to an image that is not packaged.

The source is usually an XHTML img src. This may be a cover, figure, map, or decorative image removed during compression.

If the image exists under one obvious alternate name, align the path; if not, restore the image from the manuscript source.

A stylesheet imports a file that was moved.

CSS url() or @import can reference fonts, images, or another stylesheet with a relative path that no longer works.

Check the CSS file's folder before editing the path; relative paths are resolved from the CSS file, not from the EPUB root.

Navigation points to an old chapter file.

nav.xhtml or toc.ncx can keep a stale chapter path after an export, split, or folder rename.

Only update the nav or NCX link when the intended chapter is clear and the reading order does not change.

The OPF references a resource that was removed.

A manifest item or package-level reference can point to a file that no longer exists in the ZIP.

Remove or repair the OPF reference only after confirming whether the file is unused or should be restored.

The missing-resource message to copy

RSC_007: Referenced resource could not be found in the EPUB.

Where this missing-resource message tends to appear

KDP, Kindle Previewer, or EPUBCheck may reject an EPUB that still opens in Calibre because one packaged file points to another file that is not present at that exact internal path.

What it means

The problem is usually an exact-path mismatch, not a broken book chapter.

A chapter, stylesheet, navigation file, NCX file, OPF entry, or image reference is asking for a file name the EPUB package cannot resolve.

The target may have been renamed, moved into another folder, written with different letter case, URL-encoded differently, or removed during an image or stylesheet cleanup. Another common case is a file that exists in the ZIP but is not declared where the OPF expects it.

Before you edit

Compare the reported EPUB path with the real package contents.

Treat the EPUB like a case-sensitive ZIP package. A path that looks harmless on macOS or Windows can still fail when KDP checks the archive exactly.

  1. 1Copy the exact missing target path from the message, including folder name, capitalization, spaces, URL-encoded characters, and anything after a # symbol.
  2. 2Find the file that contains the broken reference when the validator gives a source line, such as a chapter XHTML file, nav.xhtml, toc.ncx, a CSS file, or content.opf.
  3. 3Open the EPUB as a package and check whether the target exists at the exact path. Do not rely on a desktop folder search that ignores case.
  4. 4If a similar file exists, compare case, spaces, percent encoding, moved folders, and ../ relative path segments before changing the reference.
  5. 5If the target exists and is part of the book, check whether content.opf declares it when the resource type requires a manifest entry.
  6. 6If the file is truly missing, restore it from the source project or remove the broken reference instead of inventing a replacement.

Why KDP checks it

Why KDP and EPUBCheck care about the missing path.

EPUBCheck

EPUBCheck checks EPUB 2 and EPUB 3 files against the official rules and reports package, markup, link, and file-reference problems.

EPUB 3.3 package rules

The OPF file is the EPUB's map: metadata, file list, reading order, and navigation wiring. KDP and EPUBCheck use it to decide whether the book package is coherent.

Can this be fixed safely?

When this missing-resource error is safe to repair.

When automatic repair is safe

EPUB Fixer can treat this as safe only when the missing target has one clear match, such as Cover.jpg versus cover.jpg, an encoded-space mismatch, or a resource that exists and only needs a manifest or reference alignment.

When you need manual review

If the target image, CSS, XHTML, nav, or NCX file is truly absent, the safe fix is to restore it from the source project or remove the broken reference with intent. The tool should not create a blank image, invent a stylesheet, or guess which chapter the author meant.

Before / after example

Before: OEBPS/chapter1.xhtml links to images/Cover.jpg while the package contains images/cover.jpg. After: the reference uses the packaged path. Before: chapter1.xhtml links to images/map.png and no map image exists anywhere; that should stop for source-file repair.

Ready to retry?

Scan the EPUB if you only have the error text.

The scan is useful when the message does not clearly show whether the broken pointer is in a chapter, nav file, NCX file, stylesheet, or OPF manifest.

Upload EPUB to scan

FAQ

Questions authors ask when a resource is missing.

How do I fix referenced resource could not be found in the EPUB?

Start by locating the exact file path in the validator message, then compare it with the real files inside the EPUB package. The fix is usually safe only when there is one clear path, case, or manifest mismatch.

Why does KDP reject my EPUB if it opens locally?

Many reading apps, including Calibre, tolerate broken internal references. KDP, Kindle Previewer, and EPUBCheck are stricter because missing images, stylesheets, nav files, or XHTML targets can break the published Kindle file.

Is RSC_007 always caused by a missing image?

No. RSC_007 can come from images, CSS files, chapter XHTML files, OPF manifest entries, nav links, or NCX references. The missing target depends on which internal pointer fails.

Can EPUB Fixer repair this automatically?

It can flag the issue as safe to fix when the EPUB contains one obvious matching file or manifest entry. If the resource is truly absent, the report stops instead of inventing replacement content.

What path matters most in this error?

Use the path inside the EPUB message, not the path of the EPUB file on your computer. The broken part is usually an internal href, src, CSS url(), nav, NCX, or OPF reference.

Can I just delete the broken link?

Only when you know the resource is unused. Deleting a cover image, stylesheet, footnote file, or chapter link can make the validator quieter while damaging the book.

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