If the functionality of JFBConnect works properly, it's safe to ignore the error for now. We're aware that the fetching of the pages can erroneously fail and have an issue in our tracker to investigate.
Here's a more detailed description of what the usual cause of the problem is:
The full error coming back from Autotune is usually "Not Acceptable! An appropriate representation of the requested resource could not be found on this server. This error was generated by Mod_Security." It seems like mod_security (an Apache firewall addon) is blocking our automated tool from scanning your page. Mod_security, in general, tries to prevent 'bad' requests (malicious, automated, and various other kinds). It may be detecting our tool is automated (not a real browser) and denying it. You'll need to investigate your mod_security logs, or disable it, to let the Autotune tool perform its checks. Additionally, we recommend testing your page with other automated checkers.
-Melissa
Error Check Failing
