HTML Checking for Large Sites

Rocket Validator automatically scans your sites for accessibility issues using the W3C Validator, hosted on our own servers and integrated into our web crawler.

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The first occurrence of ID “X” was here.

Element IDs in an HTML document must be unique. The HTML validator is indicating the first occurrence of an ID that is repeated. Check the details for that issue to see web pages affected, and the elements within them, to fix that ID repetition.