Common problems


When a script in FluxBB receives form data, it checks the CGI variable HTTP_REFERER (misspelled in the HTTP standard) to make sure that the form was submitted from the correct script. The check is only made for administrators and moderators. The referrer check is a security mechanism that prevents malicious users from deceiving administrators and moderators by silently and invisibly submitting a form from an external page to one of the scripts in FluxBB.

The referrer check can fail for a number of reasons. The check relies on the variable “Base URL” from the options page in the admin interface. If “Base URL” is not correctly set, the referrer check will fail. It is also vital that you visit the forums by entering the exact URL found in “Base URL” into your browsers address bar. If “Base URL” is set to and you visit the forums by going to (note the www part), the check will fail.

Another common reason for the check to fail is that you are browsing the forum through a proxy or firewall of some sort that is stripping HTTP_REFERER from all requests. Norton Internet Security and Norton Personal Firewall are known to strip HTTP_REFERER in its default setup. Some popup/ad stoppers are also known to do this (most of them don't though).

If you have actually changed the URL to your forums though cannot edit it in the administration options (due to this error) you will need to manually alter the option:

  1. Execute the below SQL code, obviously replacing <url to your forum> with the URL to your forum.
  2. Delete the /cache/cache_config.php file so that the cache is regenerated.
UPDATE config SET conf_value = '<url to your forum>' WHERE conf_name = 'o_base_url';

Note: If you have a database prefix set you will obviously need to prefix it to the table name (config).

Error: Unable to write configuration cache file to cache directory

FluxBB requires write access to the /cache/ folder in order to cache certain settings. If PHP does not have write access you must CHMOD the folder to 777 (instructions).

Avatar uploads don't work

Similarly to the /cache/ folder, FluxBB requires write access to the /img/avatars/ folder in order to save avatars. If PHP does not have write access you must CHMOD the folder to 777 (instructions).

I've updated the database manually, but the changes have no effect

In order to decrease the load on the database server, FluxBB caches parts of the database to PHP scripts in the /cache/ directory. To update the cache simply delete all PHP scripts in the /cache/ directory. FluxBB will regenerate them when they are needed.

I enabled maintenance mode and cannot login

If you have enabled maintenance mode and accidentally logged out you will find it impossible to log back in! To remedy this you must open your configuration file (config.php) and at the end add:

define('PUN_TURN_OFF_MAINT', 1);

This will disable the whole maintenance mode feature and allow you to log in. Once logged in you should remove (or comment out) this from your configuration file again.

Changing the style/language did not work

If you change the style or language settings in the admin panel, this will not effect your (or anyone else's) style or language settings. Members are set with the forum default when they register. To change an existing members style or language you must go into their profile and change the setting there.

Debugging problems

To enable debug mode open the configuration file (config.php) and at the end add:

define('PUN_DEBUG', 1);
define('PUN_SHOW_QUERIES', 1);

Note: This will enable debug mode for everyone visiting the forum and expose the contents of SQL queries to everyone. Don't forget to remove (or comment out) the lines you added when you are done!