Can't edit settings.php in Drupal 7 - Premission Denied - Can't Write to File via Cpanel File Manager Trying to edit settings.php via Cpanel File Manager

I can CHMOD the file to anything I want and back but can't write to it.

I get the following message:  


  Could not write &#x2F;home&#x2F;testing&#x2F;public_html&#x2F;sites&#x2F;default&#x2F;settings.php: Permission denied


Do you think Apache suEXEC has anything to do with this?
As others have mentioned, you must set the permissions on the /sites/default folder. The default permissions are set to 0555, set them to 0755 for editing. Don't forget to restore the default values afterwards!