diff --git a/system/libraries/Email.php b/system/libraries/Email.php
index daa3848..728b637 100644
--- a/system/libraries/Email.php
+++ b/system/libraries/Email.php
@@ -2017,7 +2017,7 @@
 
 		$reply = $this->_get_smtp_data();
 
-		if (strpos($reply, '503') !== 0)	// Already authenticated
+		if (strpos($reply, '503') === 0)	// Already authenticated
 		{
 			return TRUE;
 		}
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 07dae1f..d805c8f 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -488,6 +488,7 @@
 -  Fixed a bug (#2239) - :doc:`Email Library <libraries/email>` improperly handled the Subject when used with ``bcc_batch_mode`` resulting in E_WARNING messages and an empty Subject.
 -  Fixed a bug (#2234) - :doc:`Query Builder <database/query_builder>` didn't reset JOIN cache for write-type queries.
 -  Fixed a bug (#2298) - :doc:`Database Results <database/results>` method `next_row()` kept returning the last row, allowing for infinite loops.
+-  Fixed a bug (#2289) - :doc:`Email Library <libraries/email>` method `_smtp_authenticate()` returned prematurely from authentication due to opposite condition check.
 
 Version 2.1.3
 =============