diff --git a/octoprint_auth_ldap/__init__.py b/octoprint_auth_ldap/__init__.py
index 53f1b28..73b18d6 100644
--- a/octoprint_auth_ldap/__init__.py
+++ b/octoprint_auth_ldap/__init__.py
@@ -7,6 +7,7 @@ from octoprint.settings import settings
 import ldap
 import ldap3
 import ldap3.utils.dn
+import ssl
 import uuid
 
 LDAP_SERVER = ldap3.Server("pool.ldap.ehlab.uk", tls=ldap3.Tls(validate=ssl.CERT_REQUIRED, version=ssl.PROTOCOL_TLSv1_2))