Changing File Permissions
From Documentation
Most file systems have methods of administering permissions or access rights to specific users and groups of users. These systems control the ability of the users affected to view or make changes to the contents of the file system.
68 Classifieds uses several folders to store images and files in and require the folder to be readable and writable by the server. In order to change the file permissions you would need to open you ftp editor and connect to your server. Once you have connected most ftp editors allow you to right click the folder and change the permissions. For 68 Classifieds you would need to edit the images, photos, thumbs, templates_c, and upload folders to 777 or read, write, execute all.
Please see the help section in your ftp editor for specific instructions on how to CHMOD a file or folder.