diff --git a/src/Thybag/Auth/SharePointOnlineAuth.php b/src/Thybag/Auth/SharePointOnlineAuth.php
index c222952..7721857 100644
--- a/src/Thybag/Auth/SharePointOnlineAuth.php
+++ b/src/Thybag/Auth/SharePointOnlineAuth.php
@@ -133,7 +133,7 @@ protected function extractAuthCookies($result){
 		// Get the two auth cookies
 		foreach($header_array as $header) {
 			$loop = explode(":",$header);
-			if (strtolower($loop[0]) == 'Set-Cookie') {
+			if (strtolower($loop[0]) == 'set-cookie') {
 				$authCookies[] = $loop[1];
 			}
 		}