This error is now occurring all the time, and thumbnail images are no longer being generated. Here's the recap from the old thread:
After a while I finally managed to capture this problem while the image wasn't showing, although it seems to be happening a LOT now for some reason.
The PHP error is: File is not a valid image: /home/xxx/public_html/wp-content/uploads/ Fatal error: Call to a member function adaptiveResize() on a non-object in /home/xxx/public_html/wp-content/plugins/special-recent-posts/lib/phpimage.php on line 42
Here's the broken image link: http://www.habitationofjustice.com/wp-content/plugins/special-recent-posts/lib/phpimage.php?width=65&height=65&rotation=no&file=L2hvbWUvaGFiaWFkYTEvcHVibGljX2h0bWwvd3AtY29udGVudC91cGxvYWRzLw==
I've compared this to the other image links and the only obvious difference I can tell is that the broken one is much shorter. Any help appreciated!