Sugar clients using the LinkedIn Sales Navigator plugin may experience connectivity issues if their SugarCRM instance is hosted on a server that is not publicly accessible, such as one using a local/private domain or requiring a VPN. LinkedIn has confirmed this is due to a bug in their validation logic and is working on a fix. We have provided LinkedIn a list of the known affected customers so the LinkedIn team can apply a workaround until the bug is addressed.
If you are still experiencing these issues, please file a ticket with the LinkedIn Developer Support portal, mentioning that you are affected by the .local domain bug.