diff --git a/index.php b/index.php
index 1712a7d..a378266 100644
--- a/index.php
+++ b/index.php
@@ -218,6 +218,7 @@
 	{
 		if ( ! is_dir(BASEPATH.$application_folder.'/'))
 		{
+			header('HTTP/1.1 503 Service Unavailable.', TRUE, '503');
 			exit('Your application folder path does not appear to be set correctly. Please open the following file and correct this: '.SELF);
 		}
 
@@ -233,6 +234,7 @@
 	{
 		if ( ! is_dir(APPPATH.'views/'))
 		{
+			header('HTTP/1.1 503 Service Unavailable.', TRUE, '503');
 			exit('Your view folder path does not appear to be set correctly. Please open the following file and correct this: '.SELF);
 		}
 
diff --git a/system/core/Common.php b/system/core/Common.php
index 2f9c4ff..225227d 100644
--- a/system/core/Common.php
+++ b/system/core/Common.php
@@ -177,6 +177,7 @@
 		{
 			// Note: We use exit() rather then show_error() in order to avoid a
 			// self-referencing loop with the Excptions class
+			set_status_header(503);
 			exit('Unable to locate the specified class: '.$class.'.php');
 		}
 
@@ -243,6 +244,7 @@
 		// Fetch the config file
 		if ( ! file_exists($file_path))
 		{
+			set_status_header(503);
 			exit('The configuration file does not exist.');
 		}
 
@@ -251,6 +253,7 @@
 		// Does the $config array exist in the file?
 		if ( ! isset($config) OR ! is_array($config))
 		{
+			set_status_header(503);
 			exit('Your config file does not appear to be formatted correctly.');
 		}
 
diff --git a/system/core/Input.php b/system/core/Input.php
index 7a16e51..3339d97 100755
--- a/system/core/Input.php
+++ b/system/core/Input.php
@@ -592,6 +592,7 @@
 	{
 		if ( ! preg_match('/^[a-z0-9:_\/-]+$/i', $str))
 		{
+			set_status_header(503);
 			exit('Disallowed Key Characters.');
 		}