diff --git a/system/libraries/Session/drivers/Session_files_driver.php b/system/libraries/Session/drivers/Session_files_driver.php
index 04562b2..32aeab6 100644
--- a/system/libraries/Session/drivers/Session_files_driver.php
+++ b/system/libraries/Session/drivers/Session_files_driver.php
@@ -1,4 +1,4 @@
-<?php
+r<?php
 /**
  * CodeIgniter
  *
@@ -112,10 +112,16 @@
 	 */
 	public function open($save_path, $name)
 	{
-		if ( ! is_dir($save_path) && ! mkdir($save_path, 0700, TRUE))
+		if ( ! is_dir($save_path))
 		{
-			log_message('error', "Session: Configured save path '".$this->_config['save_path']."' is not a directory, doesn't exist or cannot be created.");
-			return FALSE;
+			if ( ! mkdir($save_path, 0700, TRUE))
+			{
+				throw new Exception("Session: Configured save path '".$this->_config['save_path']."' is not a directory, doesn't exist or cannot be created.");
+			}
+		}
+		elseif ( ! is_writable($save_path))
+		{
+			throw new Exception("Session: Configured save path '".$this->_config['save_path']."' is not writable by the PHP process.");
 		}
 
 		$this->_config['save_path'] = $save_path;