How to stop "featured image" thumbnail generation?

There’s 4 types of thumbnails generated by WordPress on media upload

Not quite correct. Only the first three are generated by WordPress core. The 4th (Featured Image) is generated via your theme. You need to edit your theme’s functions.php file and remove the custom post_thumbnail. Try looking for add_image_size.

I’ve got exactly the same issue and I can’t find that within my functions.php either. Can someone help with this, please?

Sorry for not replying sooner. I found this line, tried to remove it and it pretty much disabled the site. How do I ‘deactivate’ it, please?

<?php if ( function_exists(“add_theme_support”) ) { add_theme_support(“post-thumbnails”); } ?>

If I do that, though, for some reason this is what I get, as it makes the site crash:

http://dvdfever.co.uk/dvdfever/wp-content/uploads/2011/06/dvdfevercrash.jpg

Thanks, but I’m not sure. I’ve just realised that they have a forum so I’ve posted a topic on there to see if they know. I’ll report back if I get any joy. Wish me luck 🙂