# EPUBCheck OPF-018: unneeded remote-resources, how to fix it

Source: https://epubcc.com/epubcheck/opf-018/ (updated 2026-11-04)

EPUBCheck OPF-018 is a warning message: “The "remote-resources" property was declared in the Package Document, but no reference to remote resources has been found.” A manifest item declares remote-resources, but EPUBCheck found no reference to a remote resource in it. The property tells reading apps that the document needs the network, so it should only be there when it is true.

- Official message (EPUBCheck 5.4.0): The "remote-resources" property was declared in the Package Document, but no reference to remote resources has been found.
- Default severity: Warning

## Typical causes

- The remote image, font, audio or video was removed or copied into the EPUB, but the property stayed.
- A template manifest that declared remote-resources on every document.
- A tool that adds the property by default.

## How to fix it

1. Find the manifest item EPUBCheck points to.
2. Confirm the document no longer loads anything from an http or https address.
3. Remove remote-resources from that item's properties attribute, keeping any other properties.

## When it's not this

If the document uses scripts, EPUBCheck reports OPF-018b instead, because a script could load the resource.

## Sources

- EPUB 3.3, §D.6.4 remote-resources: https://www.w3.org/TR/epub-33/#sec-remote-resources (read 2026-11-04)

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