Match the report title.
Look for "OPF dcterms:modified metadata is missing" or the closest title above. Keep the original EPUBCheck, KDP, or Kindle Previewer wording if it differs.
EPUB error guide
dcterms:modified missing in EPUB
Use this when EPUBCheck, Kindle Previewer, or a publishing platform points to missing, duplicated, or malformed dcterms:modified metadata in the OPF package file.
You see
A modified metadata error.
Upload when the message names dcterms:modified, package metadata, OPF metadata, or EPUB 3 modified date validation.
You get
The OPF path and repair boundary.
The report shows the package file, existing modified metadata state, original message, and whether a checked metadata repair is safe.
Do not upload
Retailer listing metadata.
Sales page title, author, keywords, categories, description, ISBN ownership, and platform metadata are not OPF package repairs.
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 these report titles
- OPF dcterms:modified metadata is missing
- package dcterms:modified meta element
- EPUB modified metadata is duplicated or malformed
- EPUB 3 OPF metadata validation error
Use this guide when
Your message matches "OPF dcterms:modified metadata is missing" 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.
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 dcterms:modified report should show.
A useful report should make the package metadata state explicit before any repair.
OPF file
The content.opf or package document path where metadata is stored.
Current state
Missing, duplicated, malformed, or already present modified metadata.
Original message
The EPUBCheck, Kindle Previewer, KDP, or platform wording that named dcterms:modified.
Decision
Checked repair, manual metadata review, or unsupported package state.
A safe repair only touches package metadata and must pass EPUBCheck again.
2. Next step
Choose package metadata repair or manual metadata review.
Most dcterms:modified cases are small, but duplicated or malformed package metadata can still need a human decision.
Upload scan
Use this when the validator names dcterms:modified.
The scan finds the OPF file and checks the metadata state before repair.
Checked repair
Use this when the modified field is simply missing.
A package timestamp can be added when the OPF structure is clear and the repaired EPUB passes EPUBCheck.
Manual review
Use this when metadata is duplicated or malformed.
Open the OPF when several values, invalid package markup, or competing metadata entries make the safe value unclear.
3. Concrete path example
A typical missing modified metadata issue.
The blocker lives in the OPF package document, not in the store dashboard.
Validator: OPF package metadata is missing dcterms:modified. Report: Affected file: OEBPS/content.opf Current state: no <meta property="dcterms:modified"> value found Decision: repairable when the OPF metadata block is otherwise valid Second check: run EPUBCheck again before retrying upload
If the OPF contains several conflicting modified values or invalid XML around metadata, review the package manually.
Quick decision
Decide whether this is a simple OPF metadata repair.
This page exists because metadata errors show in local stats and platform messages, but it stays limited to OPF package metadata.
Good fit
The modified metadata field is missing.
The scanner can add or normalize the required package metadata only when the OPF structure is clear.
Manual fit
There are several or malformed metadata values.
The report can show the OPF path and current state, but a person should inspect invalid package markup.
Not this tool
You want to change store metadata.
Retailer title, author, ISBN ownership, categories, keywords, descriptions, and listing data are outside this repair.
Start here
Check the OPF metadata field before changing sales metadata.
dcterms:modified is package metadata inside the EPUB. It is not the same as KDP, Kobo, or store listing metadata. Start with the OPF file named by the report or validator.
What it means
dcterms:modified is a metadata value inside the EPUB OPF package document. Validators use it as part of EPUB 3 package validation.
Can it be fixed automatically?
EPUB Fixer can help when the OPF package is valid enough to add or normalize one modified metadata field and the repaired EPUB passes EPUBCheck again.
What to check next
Find the OPF package file named by the report or container.xml.
What not to assume
It does not choose retailer metadata, ISBN ownership, title or author fields, categories, keywords, descriptions, publication dates, or platform listing values.
Common situations
Common dcterms:modified cases.
Start from the metadata state in content.opf.
No modified timestamp exists in the OPF.
Some exporters leave out the EPUB 3 modified metadata field.
Add only the package metadata field and run EPUBCheck again.
Several modified metadata values exist.
A source workflow may duplicate metadata during repeated exports.
Review the OPF manually before removing or normalizing values.
The metadata block is malformed.
Invalid XML around metadata can make the modified field appear missing or unreadable.
Fix the OPF markup first, then revalidate.
dcterms:modified messages this page can help with
dcterms:modified missing in EPUB: OPF package metadata missing, duplicated, or malformed modified timestamp.
Where modified metadata errors appear
EPUBCheck, Kindle Previewer, KDP, Apple Books, Google Play, Draft2Digital, Kobo, or another platform reports a package metadata issue involving dcterms:modified or modified metadata.
What it means
The package can be missing a required modified timestamp even when the book opens.
dcterms:modified is a metadata value inside the EPUB OPF package document. Validators use it as part of EPUB 3 package validation.
Common causes include older exporters, repeated source exports, stripped metadata, duplicated metadata blocks, malformed OPF XML, or package files created without the required modified timestamp.
Before you edit
Check content.opf before editing visible book details.
Do not change title, author, description, or ISBN fields in a platform dashboard to fix this. The issue is usually in the OPF metadata block.
- 1Find the OPF package file named by the report or container.xml.
- 2Check the metadata block for meta property="dcterms:modified".
- 3Check whether the field is missing, duplicated, malformed, or surrounded by invalid XML.
- 4Repair only package metadata, then run EPUBCheck again.
- 5Do not change retailer listing metadata to fix an OPF package metadata error.
- 6Use manual review when the OPF has several conflicting metadata states.
Why KDP checks it
Why EPUBCheck and publishing tools check modified metadata.
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.
EPUBCheck
EPUBCheck checks EPUB 2 and EPUB 3 files against the official rules and reports package, markup, link, and file-reference problems.
Can this be fixed safely?
When dcterms:modified can be repaired here.
When automatic repair is safe
EPUB Fixer can help when the OPF package is valid enough to add or normalize one modified metadata field and the repaired EPUB passes EPUBCheck again.
When you need manual review
It does not choose retailer metadata, ISBN ownership, title or author fields, categories, keywords, descriptions, publication dates, or platform listing values.
Before / after example
Before: content.opf has no meta property for dcterms:modified. After: a valid package metadata value is present and EPUBCheck passes again. Before: several conflicting metadata values exist; review the OPF manually.
Ready to retry?
Scan the EPUB for OPF modified metadata.
Upload the same EPUB that produced the message. The report can show whether the OPF has no modified timestamp, several competing values, or malformed metadata that needs manual review.
Upload EPUB to scanFAQ
Questions authors ask about dcterms:modified errors.
Is dcterms:modified the same as my KDP publication date?
No. It is OPF package metadata inside the EPUB file. KDP listing dates and retailer metadata are separate.
Can EPUB Fixer repair missing dcterms:modified?
Yes, when the OPF package is otherwise clear and the repaired EPUB passes EPUBCheck again.
What if there are several modified metadata values?
The report should stop for manual review because removing the wrong package value can hide a deeper OPF metadata problem.
Should I edit title, author, or ISBN to fix this?
No. This error is about the OPF modified metadata field, not visible book listing fields.
Related EPUB error guides
- OPF_030 unique-identifier was not found
- OPF_029 manifest media-type mismatch
- OPF_003 item is not declared in the OPF manifest
- OPF_048 package is missing unique-identifier
- OPF_049 item id was not found in the manifest
- Mimetype compressed EPUB and invalid mimetype contents
- OPF rootfile path mismatch
- container.xml missing in EPUB
- PKG_006 mimetype file entry is missing or not first