Template:Set file permissions From Online Manual
Set File/Folder Permissions
After the install archive has been uploaded and extracted, you need to set the files' permissions. This is commonly done by use of the Unix utility CHMOD. The correct CHMOD value for SMF folders is either 777, 775 or 755, and 666 or 644 usually for files, depending on your hosting service. There are two methods for this step, the method used depends on the hosting service that you use.
Setting File Permissions With the Installer
The SMF installer can set file permissions simply and easily. Navigating to the directory where SMF is located should redirect you to the install.php file and prompt the installer. For example: www.yourdomain.com/forum/install.php. If the installer detects files that need their permissions adjusted it will prompt for FTP details so it can CHMOD the files it requires for the install. This may not work on some servers.
Setting File Permissions With FTP
Using a control panel or FTP client, file permissions can be changed quickly and easily. Usually, FTP programs will allow permissions to be changed by right-clicking files/directories and selecting "Properties", "Attributes" or "Permissions". The desired numerical value can be entered, or if provided, check boxes can be changed.
The following files and directories must be writable. Depending on how your server is set up, this could mean that they must have CHMOD values of 644, 664 or 666 for files, and 755, 775 or 777 for folders:
If the permission on your files or folders does not make them writable, the SMF installer will report the problem. In that case, use your FTP client or host panel to reset the permissions for the files or folders the installer reports.
Please note: On some servers, the 777 value may cause Internal Server Errors (ISEs) or similar errors. If an ISE or other error has occured on the server, the administrator may change the value one step back, to 755.