KiCad stores user settings (or preferences) and library tables for the user in a system specific location. The default paths are:
- Unix (Linux etc.): The user’s home directory + .config/kicad/ (= $HOME/.config/kicad/)
- Windows XP: “C:\Documents and Settings\username\Application Data” + kicad\ (= %appdata%\kicad)
- Windows Vista & later: “C:\Users\username\AppData\Roaming” + kicad\ (= %appdata%\kicad)
- OSX: The user’s home directory + /Library/Preferences/kicad/
When KiCad is started it reads the environment variable KICAD_CONFIG_HOME. If it is set the value is used instead of the default path.
There are several files in this folder. The files are human readable and can be edited with a text editor. The file names are mostly self-explanatory.
Fp-lib-table and sym-lib-table are the files which can be seen in Prefrerences->Manage Footprint/Symbol Libraries dialog’s Global Libraries section. By default when KiCad is run for the first time those two files are copied from KiCad installation to the user specific setup if they are found from KiCad installation.
If some files are deleted KiCad won’t find them the next time it’s run and recreates them from scratch. Deleting everything is effectively the same as running KiCad for the first time.