Have you tried:
– deactivating all plugins to see if this resolves the problem. If this works, re-activate the plugins one by one until you find the problematic plugin(s).
– switching to the Twenty Twelve theme to rule out any theme-specific problems.
– resetting the plugins folder by FTP or PhpMyAdmin. Sometimes, an apparently inactive plugin can still cause problems.
– re-uploading all files & folders – except the wp-content folder – from a fresh download of WordPress. Make sure that you delete the old copies of files & folder before uploading the new ones.
Checking your error logs for clues might also help to pinpoint the problem.
Yes, as soon as somebody pays for my time to do all that. Nevermind.
WordPress is free software and this free, volunteer-staffed forum is the only support resource available via wordpress.org. We don’t fix your site. We help you fix it. If you cannot manage this yourself, perhaps you need to consider hiring someone to carry out the work for you.
In the meantime, we don’t have any magic bullets for you. Just a series of troubleshooting steps deliberately designed to locate the root cause as quickly as possible by first removing the most obvious and common culprits. But if you cannot work with us on them,. then we cannot help you.
I get the same message, but most of what I have found to be causing it has been plugins. I checked and could not find the file in a fresh install of the software. I have been reaching out to module developers to see about resolving version dependency issues. The responses have been positive. I am looking forward to the period of time when it all works together, before I have to do it all again on the next version >_< heh, at least it keeps my skills current.
