# EPUBCheck OPF-025: Property value list … is not allowed…

Source: https://epublab.com/epubcheck/opf-025/ (updated 2026-11-03)

EPUBCheck OPF-025 is an error message: “Property value list "…" is not allowed, only one value must be specified.” A metadata property that takes a single value was given a list of values.

- Official message (EPUBCheck 5.4.0): Property value list "%1$s" is not allowed, only one value must be specified.
- Default severity: Error

## Typical causes

- Several space-separated values in a property meant to hold one, for example two layout values in one rendition meta element.

## How to fix it

- Keep a single value. If you need different values for parts of the book, set them per item in the spine where the property allows it.

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