diff --git a/system/helpers/url_helper.php b/system/helpers/url_helper.php
index 57208c9..b1f5ecc 100644
--- a/system/helpers/url_helper.php
+++ b/system/helpers/url_helper.php
@@ -534,7 +534,7 @@
 		}
 
 		// IIS environment likely? Use 'refresh' for better compatibility
-		if (DIRECTORY_SEPARATOR !== '/' && $method === 'auto')
+		if ($method === 'auto' && isset($_SERVER['SERVER_SOFTWARE']) && strpos($_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS') !== FALSE)
 		{
 			$method = 'refresh';
 		}
diff --git a/user_guide_src/source/helpers/url_helper.rst b/user_guide_src/source/helpers/url_helper.rst
index 3054540..8de7817 100644
--- a/user_guide_src/source/helpers/url_helper.rst
+++ b/user_guide_src/source/helpers/url_helper.rst
@@ -303,7 +303,7 @@
 
 The optional second parameter allows you to force a particular redirection
 method. The available methods are "location" or "refresh", with location
-being faster but less reliable on Windows servers. The default is "auto",
+being faster but less reliable on IIS servers. The default is "auto",
 which will attempt to intelligently choose the method based on the server
 environment.