On file and directory permission and ownership

Intro to setting File Permissions

 * chmod
 * What is installer/package manager FTP path
 * What is FTP
 * How do I use FTP
 * Using an FTP client to examine and change individual file permissions
 * Using an FTP client to find out who owns "your" files and directories.

Who is the webserver? Who is php?

 * nobody (when?)
 * someone other than you (www-data on Ubuntu)
 * You, if suphp or suExec is installed and properly configured.

Things that can go wrong

 * You install SMF via FTP so the files belong to you, but the webserver runs as someone other than you, or nobody, and so it cannot edit files via Package Manager
 * You install SMF via FTP so the files belong to you, and the webserver is supposed to run as you, but it has "accidentally" caused some files created via Package Manager to be created that are not owned by you, and now neither it nor you can do anything with them.
 * Other cases?

Some Common Problems
Cases
 * Package Manager says it installed a mod correctly, but the mod is obviously not there
 * Cause
 * Solution
 * Package Manager syas it installed a mod correctly, and the mod seems to be only half there
 * Cause
 * Solution