Captcha is broken here with 7.5. I've tried the prior suggestions but don't have an answer. Was working with GD2 here on 7.4.2 (Windows server). Imagemagick is not installed.
Other images are fine, and the backgrounds can be loaded directly in a browser, but only a red x appears in IE or a blank box in FireFox.
The properties of the non-displaying image say that the URL is forums/ubbthreads.php?ubb=captcha&id= followed by what look like the entire source listing of the main forum page.
