What causes "Unable to load "%s": " in symfony/translation?

Validate the XLIFF file with xmllint or an XML editor and fix syntax errors.

symfony/translation · error · InvalidResourceException

Unable to load

Error message

Unable to load "%s":

What it means

XmlUtils::parse()/loadFile() failed to produce a DOM document (malformed XML, unreadable file, or invalid XML); the loader wraps the underlying exception (InvalidArgumentException, XmlParsingException, or InvalidXmlException) in an InvalidResourceException with this prefix. The original message is appended after the colon.

Solutions

Validate the XLIFF file with xmllint or an XML editor and fix syntax errors.
Read the chained exception message (after the colon) to locate the exact XML problem (line/column).
Re-export the file from the translation tool ensuring valid XML and UTF-8 encoding.
Run the schema validation separately (XliffUtils::validateSchema) to confirm XML well-formedness first.

Defensive patterns

Strategy: try-catch

Validate before calling

$xml = @file_get_contents($resource);
if (false === $xml) { throw new \RuntimeException('Unreadable resource'); }
if (false === simplexml_load_string($xml)) { throw new \RuntimeException('Malformed XML in '.$resource); }

Try / catch

try {
    $catalogue = $loader->load($resource, $locale);
} catch (InvalidResourceException $e) {
    $this->logger->error('XLIFF load failed', ['resource' => $resource, 'reason' => $e->getMessage(), 'previous' => $e->getPrevious()?->getMessage()]);
    throw $e;
}

Prevention

Always inspect $e->getPrevious() for the precise XML error (line/column).
Lint XLIFF files with xmllint in CI before shipping.
Export files in UTF-8 from translation tools.
Avoid hand-editing XLIFF without re-validating.

When it happens

Trigger: Calling XliffFileLoader::load() with an XLIFF string or file containing syntactically invalid XML, or a file XmlUtils cannot load (unreadable permissions, encoding issues).

Common situations: Hand-edited XLIFF files with unclosed tags; files exported by third-party tools with invalid characters; truncated downloads; wrong file encoding (not UTF-8).

Related errors

AI-assisted analysis of symfony/translation@ae9e8a51bc (2026-09-15). Data as JSON: /api/errors/89911edeb36200ec. Report an issue: GitHub.

Appendix: source

Thrown at Loader/XliffFileLoader.php:59

            }

            if (!file_exists($resource)) {
                throw new NotFoundResourceException(\sprintf('File "%s" not found.', $resource));
            }

            if (!is_file($resource)) {
                throw new InvalidResourceException(\sprintf('This is neither a file nor an XLIFF string "%s".', $resource));
            }
        }

        try {
            if ($this->isXmlString($resource)) {
                $dom = XmlUtils::parse($resource);
            } else {
                $dom = XmlUtils::loadFile($resource);
            }
        } catch (\InvalidArgumentException|XmlParsingException|InvalidXmlException $e) {
            throw new InvalidResourceException(\sprintf('Unable to load "%s": ', $resource).$e->getMessage(), $e->getCode(), $e);
        }

        if ($errors = XliffUtils::validateSchema($dom)) {
            throw new InvalidResourceException(\sprintf('Invalid resource provided: "%s"; Errors: ', $resource).XliffUtils::getErrorsAsString($errors));
        }

        $catalogue = new MessageCatalogue($locale);
        $this->extract($dom, $catalogue, $domain);

        if (is_file($resource) && class_exists(FileResource::class)) {
            $catalogue->addResource(new FileResource($resource));
        }

        return $catalogue;
    }

    private function extract(\DOMDocument $dom, MessageCatalogue $catalogue, string $domain): void
    {

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