I'm running a Silverstripe 2.4.7 site, and image resampling when inserting images into the page was working. Suddenly, it has stopped generating resampled versions and storing them in _resampled. Instead, it inserts the full sized image into the page, and relies on the width and height tags.
Does anyone know what could have gone wrong? I've seen a few mentions of this problem, but no solutions that I can use. I've already checked the folder permissions, so it has nothing to do with that.