diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index 3c27686a89..2be0244870 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -230,7 +230,7 @@ class MatrixFederationHttpClient(object):
             if not try_trailing_slash_on_400:
                 # Received an error >= 300. Raise unless we're retrying
                 raise e
-        except:
+        except Exception as e:
             raise e
 
         # Retry with a trailing slash if we received a 400 with