diff --git a/emmett/http.py b/emmett/http.py
index da44e28b..c96aa3ea 100644
--- a/emmett/http.py
+++ b/emmett/http.py
@@ -221,7 +221,7 @@ async def asgi(self, scope, send):
                 return
             self._headers.update(self._get_stat_headers(stat_data))
             await self._send_headers(send)
-            if 'http.response.pathsend' in scope['extensions']:
+            if 'http.response.pathsend' in scope.get('extensions', {}):
                 await send({
                     'type': 'http.response.pathsend',
                     'path': str(self.file_path)