Facebook plug-in is abolished in SmartJobBoard ver. 4.2 and transfered to the main functionality of the software. It is not considered as plugin anymore but it is included in the software.
You can set up Facebook settings on the Facebook page of Admin Panel.
If you use version lower than 4.2 please refer to following article:
Facebook plug-in allows users easily register/log in to your job board site using their accounts on Facebook, auto fill and synchronize their resume, and 'like' particular jobs/resumes posted on the job board.
To make settings for the Facebook plug-in go to Admin Panel > System Configuration > Plugins > FacebookSocialPlugin Settings.
On the opened page you will see the following form:
Facebook appID Key and App Secret Key - follow the given instructions to get your own appID and Secret Keys and then paste them to these fields;
When making settings for your application, make sure to enter a website URL in 'Website' field, otherwise the application will not work properly:
User Group - select Users Group(s) which users should be able to use Facebook connect option;
Allow Resume auto filling/synchronizing for Job Seekers - check this box to allow job seekers autofilling/synchronizing their resumes with facebook profile;
Display “Like” FaceBook icon for Jobs - enable this setting to allow users to "like" jobs posted on the job board;
Display “Like” FaceBook icon for Resumes - enable this setting to allow users to "like" resumes posted on the job board;
Make sure to press the "Save" button under the form to save the settings you made.
To see the description of the way Facebook Connect add-on works for users, click here