Match the report title.
Look for "EPUBCheck RSC-005 duplicate ID" or the closest title above. Keep the original EPUBCheck, KDP, or Kindle Previewer wording if it differs.
EPUB error guide
EPUBCheck RSC-005 duplicate ID
Use this page only when the full RSC_005 message names a duplicate id. The scan can preserve the file, line, and error evidence, but choosing which id to rename remains manual.
You see
The message matches this guide.
Choose this guide when your KDP, Kindle Previewer, or EPUBCheck wording matches "EPUBCheck RSC-005 duplicate ID" or a close variant.
You get
An affected EPUB path and decision.
The report points to the package, OPF, nav, XHTML, resource, anchor, metadata, or ZIP area behind the message.
Do not upload
The issue is outside EPUB structure.
Use the source tool or publishing workflow for DOCX, PDF, KPF, fixed-layout, DRM, cover design, KDP listing, or review problems.
Scan when the message does not name the affected path. The report shows affected paths and repair decisions, not manuscript text.
No signup before the scan report.Checks EPUB package paths, not manuscript text.Repair download only after EPUBCheck passes again.
Need fixed-layout, DRM, or source-file help? Check unsupported or review-first EPUB cases.
Match these report titles
- EPUBCheck RSC-005 duplicate ID
- RSC_005 error while parsing file duplicate ID
- duplicate ID
- duplicate ids
Use this guide when
Your message matches "EPUBCheck RSC-005 duplicate ID" 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
Decide if this report item matches.
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.
A useful report does not stop at the error name. It connects the message to an internal file and a next action.
Check the affected file first.
Use the Affected area, Source file, Target file, or Problem type rows before editing OPF, nav, XHTML, CSS, or image paths.
Follow the repair decision.
Repairable means one clear structural change. Needs review or Not supported means use the named file, source project, or platform step.
Keep with your repair note.
Copy these fields from the report instead of rebuilding the fix from memory.
Source file
Target path or field
Original error
Repair decision
Next step
1. Example report output
What the RSC_005 report should show.
A useful duplicate id report should show the repeated value and whether links make automatic repair risky.
EPUBCheck message
ERROR(RSC-005): OEBPS/Text/chapter2.xhtml(88,12): Error while parsing file: duplicate ID "note-4".
KDP / Previewer wording
The EPUB contains invalid XHTML or a duplicate anchor that prevents reliable conversion.
EPUB Fixer report
chapter2.xhtml contains the reported duplicate id at the EPUBCheck location. The result stays manual because links may depend on either occurrence.
Do this next
Rename and update links only when the intended target for each duplicate is clear.
Do not do this
Do not delete one id before checking TOC links, footnotes, endnotes, backlinks, and internal anchors.
EPUB Fixer stops at manual review for duplicate IDs because choosing which occurrence should keep the id can change where readers land.
2. Next step
Choose the next step from the duplicate id context.
RSC_005 can be a small XHTML cleanup or a navigation-risk problem.
Scan first
You only have the duplicate id value.
Find every occurrence and every href, nav, toc, footnote, or backlink that points to the same id.
Manual edit
One duplicate looks accidental.
Confirm that judgment in the XHTML and every incoming link, then rename the accidental occurrence and update affected links in the source tool or EPUB editor.
Manual review
The duplicate affects notes or navigation.
Stop when footnotes, endnotes, repeated headings, MathML, semantic markup, or reading order are involved.
3. Concrete path example
A typical RSC_005 duplicate id problem.
The report should connect the repeated id to the links that might break.
EPUBCheck: ERROR(RSC-005): OEBPS/Text/chapter2.xhtml(88,12): Error while parsing file: duplicate ID "note-4". Report: File: OEBPS/Text/chapter2.xhtml Duplicate id: note-4 Check next: search XHTML, nav.xhtml, toc.ncx, footnotes, and backlinks for #note-4 Fix decision: manual review before either id changes After: validate XHTML and EPUBCheck again
If both copies are footnote targets or reader navigation anchors, passing EPUBCheck is not enough; the links still need to land in the right place.
Quick decision
Decide whether RSC_005 is a simple duplicate or a link-risk issue.
The more links that point to the id, the less safe an automatic rename becomes.
Scan first
Find every occurrence and reference.
Use the file path and id value from EPUBCheck, then search nav, toc, XHTML links, footnotes, and backlinks.
Manual fix
One duplicate is unused and accidental.
Confirm that no TOC, note, backlink, or internal link needs it, then rename or remove it in the source or EPUB editor and validate again.
Stop
The duplicate controls navigation or notes.
Do not auto-rewrite footnotes, endnotes, semantic markup, repeated headings, MathML, or reading-order anchors.
Start here
Start with the XHTML file and duplicate id.
RSC_005 is a broad parser code. Use this guide when the complete message specifically says duplicate ID, then check whether TOC links, footnotes, backlinks, or repeated headings depend on that value.
What it means
IDs are supposed to be unique within a document. Duplicate IDs can break links, footnotes, TOC anchors, and reading system behavior.
Can it be fixed automatically?
EPUB Fixer does not automatically rename or remove duplicate IDs. The report keeps the affected XHTML path and error evidence together so you or an EPUB editor can trace every dependent link before changing the file.
What to check next
Find the XHTML file named in the validator message before editing any other file.
What not to assume
The tool must not choose between repeated headings, footnotes, backlinks, MathML, semantic markup, or reader destinations because changing the wrong id can redirect navigation while still clearing the validator message.
Common situations
Common RSC_005 duplicate id cases.
Duplicate ids often appear after editing or conversion, but the safe action depends on what points to the id.
Two headings use the same generated id.
A converter created id="chapter-title" more than once in the same XHTML file.
Rename only if TOC and internal links can be updated cleanly.
Footnotes were copied between chapters.
The same note id appears twice and backlinks may return to different paragraphs.
Manual review is safer unless every footnote link target is obvious.
A section was duplicated during editing.
Copy-paste preserved old anchors inside a repeated block.
Check whether the duplicate block is intended content before editing ids.
Malformed XHTML is reported near a duplicate id.
The parser may stop at the id while the real issue is broken surrounding markup.
Inspect the local XHTML before making id-only changes.
The RSC_005 duplicate id error text
RSC_005: Error while parsing file. Duplicate ID.
Where RSC_005 appears in EPUBCheck and Kindle checks
EPUBCheck cannot parse an XHTML file cleanly because the same id appears more than once, or markup is malformed.
What it means
RSC_005 usually starts inside one XHTML file.
IDs are supposed to be unique within a document. Duplicate IDs can break links, footnotes, TOC anchors, and reading system behavior.
Duplicate IDs often appear after copy-paste editing, automatic export bugs, or manual XHTML edits.
Before you edit
Trace the duplicate id and every link that targets it.
The safe question is not just whether the id is repeated. It is whether renaming one copy can preserve the intended reading target and all backlinks.
- 1Find the XHTML file named in the validator message before editing any other file.
- 2Search that XHTML file for the duplicate id value or malformed markup reported by EPUBCheck.
- 3Check whether nav.xhtml, toc.ncx, footnotes, endnotes, or internal links point to that id.
- 4Rename or remove a duplicate only when you can update every affected link without changing the reading target.
- 5Avoid automatic changes when the duplicate id affects footnotes, semantic markup, repeated headings, or reading order.
Why KDP checks it
Why duplicate ids break EPUB validation.
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?
Why duplicate ID stays a manual repair.
When automatic repair is safe
EPUB Fixer does not automatically rename or remove duplicate IDs. The report keeps the affected XHTML path and error evidence together so you or an EPUB editor can trace every dependent link before changing the file.
When you need manual review
The tool must not choose between repeated headings, footnotes, backlinks, MathML, semantic markup, or reader destinations because changing the wrong id can redirect navigation while still clearing the validator message.
Before / after example
Before: two headings use id="subhead-1". Manual next step: identify which heading each incoming link should reach, rename only the accidental duplicate, update those links, and run EPUBCheck again.
Ready to retry?
Scan to keep the RSC_005 path and evidence together.
The report can preserve the EPUBCheck file path, line, duplicate value, and manual decision. It does not automatically choose which repeated id or reader destination should change.
Upload EPUB to scanFAQ
Questions authors ask about EPUBCheck RSC-005 duplicate ID.
What does EPUBCheck RSC-005 duplicate ID mean?
It means an XHTML document contains repeated id values or malformed markup that prevents EPUBCheck from parsing the file safely. Duplicate ids can break TOC links, footnotes, and internal anchors.
Can EPUB Fixer repair duplicate ID errors automatically?
No. Duplicate ID stays manual because the tool cannot safely choose which occurrence should keep the id or where TOC links, footnotes, endnotes, and backlinks should land.
Does every RSC_005 error belong on this duplicate ID page?
No. Use this page only when the full EPUBCheck message names a duplicate id. Other RSC_005 messages may come from malformed XHTML, named entities, namespace, encoding, or other parser problems.
Why can a duplicate ID pass a local reader but fail validation?
Some readers ignore repeated ids or choose the first match. KDP, Kindle Previewer, and EPUBCheck need valid XHTML structure so links and navigation targets resolve consistently.
Should I just delete one duplicate id?
Only if no link, TOC entry, footnote, or backlink depends on it. Deleting the wrong id can pass validation while breaking reader navigation.