Systemwide Defaults

If you have installed the Wolfram System in a location where multiple users can run it (for example, on a file server or multi-user machine), then you can set up systemwide defaults for the Wolfram System front end and kernel. This is ideal for setting up the Wolfram System for use in computer labs and classrooms. If you share the directory $BaseDirectory across the network, these defaults will also take effect on local installations that use the shared $BaseDirectory.
In the pathnames that follow, replace the variables $BaseDirectory and $UserBaseDirectory with the appropriate directories for your system. To find their locations on your system, evaluate the command $BaseDirectory (or $UserBaseDirectory) in a Wolfram System notebook.
Setting Up a Configuration File for the Front End:

1.  Launch the Wolfram System and set up any changes to the front end that you need. For example, you may want to modify default file locations, language options, or menu settings.

2.  Quit the Wolfram System.

3.  Copy the file $UserBaseDirectory\FrontEnd\init.m to the directory $BaseDirectory\FrontEnd.

These settings will now be used by the front end unless overridden by the local init.m file stored in the user's $UserBaseDirectory\FrontEnd directory.
Setting Up a Configuration File for the Kernel:

4.  Launch the Wolfram System and create a new file.

5.  Add any Wolfram System commands that should be evaluated on startup. For example, you may want to add a function definition or display a message at startup. Enter all the commands in the same cell, separating commands with semicolons.

6.  Make this cell an initialization cell by selecting the cell bracket and then choosing Cell Cell Properties Initialization Cell.

7.  When you have finished making your changes, choose File Save and select Wolfram Language Package from the Save as type popup menu. Then save the file as $BaseDirectory\Kernel\init.m.

These commands will be evaluated when users launch the Wolfram System. If you added a function definition, that function will be available to all users.
If you have created systemwide defaults you want to carry over to new local installations, you can add lines to an installation script to copy preconfigured init.m files as part of a new installation. For information about installation scripts, see "Installing Mathematica". To copy systemwide defaults, add a line to the script similar to the line that copies the mathpass file.