If permitted by the administrator, users may attach files to their forum & private messages. The amount of files that the user can attach as well as their maximum size can be defined by the administrator on a forum by forum basis via the forum control panel. The ability to attach files to private messages can be defined by the administrator via the private messaging system controls.

In addition to specifying the size and the quantity limits the administrator may also indicate what file types can be attached to the messages using the file attachment control panel. The attached files will be matched against the FUDforum 2.3 MIME listing so that (1) a proper file icon can be assigned to the file, (2) the file download form can send the proper header to the browser, and (3) the browser can interpret the file properly.

It is also possible to restrict certain users from being able to attach files or only allow certain users to attach files using the group management system.