I get this error related to the URL_title when I submit an edit form. I’m not sure why this is a problem - I’m editing the record, not adding it, so it should just place the same url_title in the url_title field. Reviewing the Form Helper documentation now…

Aha. My bad, everyone. I had URL title in my code twice, one of which set a hardcoded value for the url_title. Which would of course generate an EE error.

This shouldn’t be an issue for anyone else. We’d only noticed it upon doing an EE update so we wondered if something had to change in the way we set up the form. Sorry to take up your time!