Search service fails after LDAP server change

Running 4.0 on Ubuntu without any issue. We had to change the LDAP server and everything worked without a problem except the search. We have tried removing the plugin and reinstalling it to no avail. This is the error we get:

*2016.03.08 21:54:01 org.jivesoftware.openfire.session.LocalOutgoingServerSession[Create outgoing session for: mydomain.com to search.mydomain.com] - Unable to create new session: Cannot create a plain socket connection with any applicable remote host. *

We use only one server. This was not happening before the LDAP change.

Any ideas?

Thanks!

Apparently, the ldap.searchFields field was empty. Adding the following and restarting the search plugin solved the problem:

Username/sAMAccountName,Name/cn,Surname/sn,Email/mail