diff --git a/lib/pop3/connection.js b/lib/pop3/connection.js
index 95fc4681..a05f3b8d 100644
--- a/lib/pop3/connection.js
+++ b/lib/pop3/connection.js
@@ -855,7 +855,7 @@ class POP3Connection extends EventEmitter {
                     return next(err);
                 }
 
-                if (!response.user) {
+                if (!response || !response.user) {
                     this.logger.info(
                         {
                             tnx: 'authfail',
@@ -867,7 +867,7 @@ class POP3Connection extends EventEmitter {
                         username,
                         'PLAIN'
                     );
-                    this.send('-ERR [AUTH] ' + (response.message || 'Username and password not accepted'));
+                    this.send('-ERR [AUTH] ' + ((response && response.message) || 'Username and password not accepted'));
                     return next();
                 }