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EPUBCheck · Package document (OPF)

EPUBCheck OPF-012: property wrong for file type

Updated:

EPUBCheck OPF-012 is an error message: “Item property "…" is not defined for media type "…".” A manifest item has a property that does not apply to its media type. Manifest properties describe what a file is or contains, and each one is only defined for certain kinds of file.

The official message

Item property "%1$s" is not defined for media type "%2$s".

Default severity
Error. The EPUB breaks a rule of the specification and is invalid. Stores and Send to Kindle may reject it, and EPUBCheck exits with status 1.
EPUBCheck version
5.4.0

%1$s, %2$s… are filled in with the file, value or element EPUBCheck found.

Typical causes

  • cover-image on a file that is not an image, such as the XHTML page that shows the cover.
  • nav on a file that is not an XHTML document.
  • svg, mathml or scripted on a file that is not a content document, such as a stylesheet or an image.

How to fix it

  1. Read the property and media type EPUBCheck names in the message.
  2. Move the property to the item it really describes, for example cover-image to the image file itself.
  3. Remove the property if no item should carry it, then run EPUBCheck again.

When it's not this

If the property simply does not exist in the vocabulary, that is OPF-027.

Terms used here

Other OPF messages

  • OPF-011 itemref can’t have both page-spread-right and page-spread-left properties.
  • OPF-013 Resource "…" is declared with MIME type "…" in content, but has MIME type "…" in the package document.
  • OPF-014 The property "…" should be declared in the OPF file.
  • OPF-015 The property "…" should not be declared in the OPF file.
  • OPF-016 The element "rootfile" is missing its required attribute "full-path".
  • OPF-007 Re-declaration of reserved prefix "…".

Sources

Message text and severity from EPUBCheck 5.4.0 (W3C, BSD-3-Clause). Explanation by EpubCC.

FAQ

What does EPUBCheck OPF-012 mean?

EPUBCheck OPF-012 is an error message: “Item property "…" is not defined for media type "…".” A manifest item has a property that does not apply to its media type. Manifest properties describe what a file is or contains, and each one is only defined for certain kinds of file.

Is OPF-012 an error?

OPF-012 is reported as error by default. The EPUB breaks a rule of the specification and is invalid. Stores and Send to Kindle may reject it, and EPUBCheck exits with status 1.