diff --git a/Slim/Environment.php b/Slim/Environment.php
index e43877e83..85d2d9a17 100644
--- a/Slim/Environment.php
+++ b/Slim/Environment.php
@@ -135,7 +135,7 @@ private function __construct($settings = null)
             if (strpos($requestUri, $scriptName) !== false) {
                 $physicalPath = $scriptName; // <-- Without rewriting
             } else {
-                $physicalPath = dirname($scriptName); // <-- With rewriting
+                $physicalPath = ltrim(dirname($scriptName), '\\'); // <-- With rewriting
             }
             $env['SCRIPT_NAME'] = rtrim($physicalPath, '/'); // <-- Remove trailing slashes