diff --git a/radicale-auth-ldap/__init__.py b/radicale-auth-ldap/__init__.py
index 23e207f..c1e7597 100644
--- a/radicale-auth-ldap/__init__.py
+++ b/radicale-auth-ldap/__init__.py
@@ -88,7 +88,10 @@ class Auth(BaseAuth):
         logger.debug("LDAP user attribute: %s" % userAttribute)
 
         logger.debug("LDAP: search user %s" % user)
-        conn.search(searchBase, userFilter.format(name=user), attributes=[userAttribute, accessGroupAttribute])
+        if (not accessGroupFilter == "None") and (not accessGroupAttribute == "None"):
+            conn.search(searchBase, userFilter.format(name=user), attributes=[userAttribute, accessGroupAttribute])
+        else:
+            conn.search(searchBase, userFilter.format(name=user), attributes=[userAttribute])
         numberOfResponseEntries = len(conn.response)
 
         logger.debug("LDAP search result: %s" % str(conn.result))