In the Phorum settings, there is an entry called "Cache Directory". On UNIX systems, the installer will have set that to the default location /tmp. The cache directory is used for storing cached data and compiled templates. You can change the location of your cache directory if you do not want the Phorum files to be in /tmp or if you see the following kind of error message:

Warning:
fopen(/tmp/tpl-default-header-a72fb9dd20915e5953aa9b07d3eb3871.php):
failed to open stream: permission denied in
/path/to/phorum/include/templates.php on line 184

If you want to change the cache directory settings, we advise you to change it to ./cache (this directory is already in the Phorum directory).

You will have to make sure that this directory is writable by the webserver. Most likely this means that you have to make it world writable. On a UNIX shell prompt, you can do this using the following commands:

shell> cd /path/to/phorum
shell> chmod 777 cache

If you do not have access to the shell prompt of the server and are using FTP to access the server, please check your FTP client's help on how to set the permissions for a directory.