Plone 5.0.8 - pas.plugins.ldap1.5.2 connection test fails

Please, I'm experiencing the following issue with pas.plugins.ldap1.5.2, Plone 5.0.8 and Ubuntu16.04.3 when trying to connect to Active Directory.

The message in the Plone interface is: ERROR: Exception in Users;

In the /opt/plone/zinstance/var/log/instance.log is:

2017-11-22T13:36:32 ERROR pas.plugins.ldap Non-LDAP error while connection test!
Traceback (most recent call last):
File "/opt/plone/buildout-cache/eggs/pas.plugins.ldap-1.5.2-py2.7.egg/pas/plugins/ldap/", line 153, in connection_test

I already replied to your issue at