Match the report title.
Look for "RSC_007: Referenced resource could not be found in the EPUB." or the closest title above. Keep the original EPUBCheck, KDP, or Kindle Previewer wording if it differs.
EPUB error guide
Use this when you already have the exact RSC_007 line. Follow the source file and missing target path before you change nav.xhtml, content.opf, chapters, images, or CSS.
Scan when the message does not name the affected path. The report shows affected paths and repair decisions, not manuscript text.
Fixed-layout, DRM, or source-workflow issue? Check unsupported or review-first EPUB cases.
Match this report title
Use this guide when
Your message matches "RSC_007: Referenced resource could not be found in the EPUB." or one of the report titles above.
Upload if
You have the exported reflowable .epub and need the affected path, file, field, or repair decision before editing.
Handle outside this tool
Use the source tool or publishing workflow for DOCX, PDF, KPF, KCB, fixed-layout, comics, image-first books, DRM, visual design, or KDP listing and approval problems.
Read the scan report
Use the report label, affected file, and repair decision together. A matching title alone is not enough if the file path or EPUB structure points to a different problem.
Look for "RSC_007: Referenced resource could not be found in the EPUB." or the closest title above. Keep the original EPUBCheck, KDP, or Kindle Previewer wording if it differs.
Use the Affected area, Source file, Target file, or Problem type rows before editing OPF, nav, XHTML, CSS, or image paths.
Repairable means one clear structural change. Needs review or Not supported means use the named file, source project, or platform step.
Copy these fields from the report instead of rebuilding the fix from memory.
1. Example report output
The report should connect the exact validator text to the source file, missing target, and repair decision.
EPUBCheck message
ERROR(RSC-007): OEBPS/nav.xhtml(12,45): Referenced resource "text/chapter-03.xhtml" could not be found in the EPUB.
KDP / Previewer wording
The EPUB contains a missing or broken internal file reference.
EPUB Fixer report
Source path OEBPS/nav.xhtml, broken target text/chapter-03.xhtml, closest match Text/chapter-03.xhtml.
Do this next
Repair only if Text/chapter-03.xhtml is the single matching chapter file, then validate again.
Do not do this
Do not point nav.xhtml to a random nearby chapter just to clear the RSC_007 line.
If several chapter files could match, stop and confirm the intended reading order before editing nav.xhtml.
2. Next step
RSC_007 is common, but the fix depends on whether the missing target is an image, CSS file, chapter, nav file, NCX entry, or OPF reference.
Upload scan
Group messages by source file first; one folder rename can create many missing-resource lines.
Manual check
Navigation repairs can change what Kindle shows in Go To, so confirm the target chapter before changing the link.
Repair summary
Send the missing target path and the original manuscript/export project so the file can be restored correctly.
3. Concrete path example
This is the kind of case that can be safe when there is only one packaged target.
Message: ERROR(RSC-007): OEBPS/nav.xhtml references text/chapter-03.xhtml Report shows: OEBPS/nav.xhtml -> text/chapter-03.xhtml Found: Text/chapter-03.xhtml Fix: update nav.xhtml only if this is the intended chapter
Do not apply this pattern when two chapter files could be valid targets.
Quick decision
The code tells you the category. The source file and target path tell you whether this is a safe path repair, a manifest problem, or a missing source asset.
Scan first
Scan the EPUB and group the errors by source file. One moved folder can create many messages, and fixing the root path is safer than editing each link blindly.
Safe fix
RSC_007 means the link points to a ZIP path that EPUBCheck cannot find. Case-only, percent-encoding, and simple relative-path mistakes can be repaired when the report shows one matching packaged file and no competing target.
Manual/source fix
If the target file is not in the EPUB, restore it from the source project or re-export. If several files look similar, do not guess; choosing the wrong image, chapter, or stylesheet can make the EPUB validate while showing the wrong content.
Start here
An RSC_007 line often contains two clues: the file being checked and the resource it cannot reach. Keep both. The repair decision depends on that pair, not just on the error code.
RSC_007 means one file inside the EPUB points to another packaged file that cannot be resolved at that exact path. The book may still display in Calibre because some readers skip the missing image, stylesheet, chapter, nav, or NCX target instead of rejecting the package.
Safe fixes include obvious path case differences, URL encoding mismatches, relative path mistakes, or missing manifest declarations when the package contains one clear target. After the change, the EPUB should pass EPUBCheck again so a different RSC_007 line is not hiding behind the first one.
Start with the file path in the error message and find the file that contains the broken link, image source, CSS url(), nav entry, NCX entry, or manifest reference.
The repair is not safe to automate when several files could match, when the referenced resource is absent from the EPUB, or when replacing it would require deciding what the book should contain. In those cases the correct fix is usually to restore the original image, CSS, XHTML, nav, or NCX file from the source project and export the book again.
Common situations
An RSC_007 in a chapter is not the same as an RSC_007 in nav.xhtml, CSS, or content.opf.
A chapter can point to ../Images/Cover.jpg while the EPUB contains images/cover.jpg. EPUB paths are case-sensitive, so a file that opens locally can still fail validation.
Compare the path from the chapter file's folder, then update the reference only when one packaged image or chapter is the clear target.
CSS url(...) paths are resolved from the stylesheet's folder, not from the chapter. A moved stylesheet can make fonts or background images look missing.
Confirm the asset exists at the resolved ZIP path and is declared in the OPF manifest before changing the CSS URL.
Chapter renames and split/merge exports often leave navigation files behind.
Fix the nav or NCX target only when the intended chapter is unambiguous; otherwise check the reading order manually.
Sometimes the target exists in the ZIP, but the package inventory or relative reference still makes validators treat it as unreachable.
Align the OPF manifest or the reference path, then run EPUBCheck again before making another edit.
A deleted image, stylesheet, or XHTML file can remain in content.opf even after the export tool removed it from the package.
Remove or correct the manifest item only after confirming the file is not used by a chapter, nav file, NCX file, or stylesheet.
RSC_007: Referenced resource could not be found in the EPUB.
KDP, Kindle Previewer, or EPUBCheck reports RSC_007 during validation, often after an export, file rename, manual ZIP edit, image optimization pass, or a retry on a file that still opens in a local reader.
What it means
RSC_007 means one file inside the EPUB points to another packaged file that cannot be resolved at that exact path. The book may still display in Calibre because some readers skip the missing image, stylesheet, chapter, nav, or NCX target instead of rejecting the package.
The broken pointer can live in XHTML href or src attributes, CSS url() values, OPF manifest references, nav links, NCX content sources, image references, or stylesheet imports. Common causes are letter-case changes, renamed folders, spaces or URL encoding differences, files moved during export, and files present in the ZIP but not wired the way the package expects.
Before you edit
Work one reported path at a time. Fixing a case mismatch is different from restoring a missing image, and both are different from an OPF manifest issue.
Why KDP checks it
EPUBCheck checks EPUB 2 and EPUB 3 files against the official rules and reports package, markup, link, and file-reference problems.
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?
Safe fixes include obvious path case differences, URL encoding mismatches, relative path mistakes, or missing manifest declarations when the package contains one clear target. After the change, the EPUB should pass EPUBCheck again so a different RSC_007 line is not hiding behind the first one.
The repair is not safe to automate when several files could match, when the referenced resource is absent from the EPUB, or when replacing it would require deciding what the book should contain. In those cases the correct fix is usually to restore the original image, CSS, XHTML, nav, or NCX file from the source project and export the book again.
Before: a nav entry points to text/chapter-03.xhtml, but the package contains Text/chapter-03.xhtml. After: the nav link uses the packaged path. Before: chapter1.xhtml references images/diagram.png and the EPUB has no diagram image; that should be restored from the manuscript source, not fabricated.
Ready to retry?
A scan can separate a simple path mismatch from a genuinely missing resource, then show whether the same EPUB has more than one broken reference.
Upload EPUB to scanFAQ
RSC_007 means an internal EPUB reference points to a file that EPUBCheck cannot resolve. It often appears in links, image sources, CSS URLs, OPF manifest items, nav files, or NCX entries.
Use the path in the EPUBCheck or KDP message as the starting point, then inspect the packaged EPUB files for the closest real match. Compare folder names, capitalization, spaces, URL-encoded characters, and whether the target is declared in the OPF manifest.
Sometimes. If the EPUB package already contains the intended file, a targeted path or manifest correction may be enough. If the file is missing, re-exporting or restoring the original source file is usually required.
Calibre and other local readers may skip or tolerate a broken image, CSS, nav, or chapter reference. KDP, Kindle Previewer, and EPUBCheck validate the package paths more strictly before accepting the file.
Kindle Previewer can report the same underlying broken reference, but the wording may differ from EPUBCheck. The important detail is the affected path and whether the referenced file exists in the EPUB.
RSC_007 usually means the referenced file path cannot be found. RSC_012 means the file exists, but the anchor after the # symbol is missing inside that file. The first check is the packaged file path; the second check is the target id inside the XHTML.
No. A broken image path, a missing CSS import, a nav link to a moved chapter, and an undeclared OPF resource can all surface as RSC_007. The affected source file and target path decide the fix.