diff --git a/emailadmin/inc/class.defaultimap.inc.php b/emailadmin/inc/class.defaultimap.inc.php
index 909f722c76..04487e29b7 100644
--- a/emailadmin/inc/class.defaultimap.inc.php
+++ b/emailadmin/inc/class.defaultimap.inc.php
@@ -525,6 +525,7 @@ class defaultimap extends Net_IMAP
 		if(empty($username))
 		{
 			if ($this->debug) error_log(__METHOD__."No username supplied.".function_backtrace());
+			if ($this->_connected) $this->disconnect(); // disconnect (if connected)
 			return false;
 		}
 		if( PEAR::isError($status = parent::login($username, $password, 'LOGIN', !$this->isAdminConnection)) ) {