diff --git a/lib/SimpleSAML/Bindings/SAML20/HTTPPost.php b/lib/SimpleSAML/Bindings/SAML20/HTTPPost.php
index 478c52e4bf413fd7368607bb053f336aa7215ded..924ed9afe343628b28032bbc4de5d401197c9414 100644
--- a/lib/SimpleSAML/Bindings/SAML20/HTTPPost.php
+++ b/lib/SimpleSAML/Bindings/SAML20/HTTPPost.php
@@ -188,9 +188,13 @@ class SimpleSAML_Bindings_SAML20_HTTPPost {
 	}
 	
 	public function decodeResponse($post) {
+		if (!isset($post["SAMLResponse"])) throw new Exception('Could not get SAMLResponse from Browser/POST. May be there is some redirection related problem on your server? In example apache redirecting the POST to http to a GET on https.');
+		
 		$rawResponse = 	$post["SAMLResponse"];
 		$relaystate = 	$post["RelayState"];
 		
+
+		
 		$samlResponseXML = base64_decode( $rawResponse );
 		
 		//error_log("Response is: " . $samlResponseXML);