In corporation you have to restrict login usernames from Facebook and Gmail.Except selected users all can able to login into Facebook or Gmail.
Prerequisites
Go to Search
Search policy: "BLOCK PARTICULAR USER LOGIN"
Go to Content Modifier: Rewrite Policies
Ensure Global Section with Enabled TRUE
Go to Rewrite Policies and make it Enable
Enter Username inside Pattern
Search policy: "BLOCK PARTICULAR USER LOGIN"
Go to Access Profiles to Enable
To test
Go to Facebook and Login
Try login to your Facebook account it will show you the below page:
Go to Gmail and Login
Try login to your Gmail account it will show you the below page: