diff --git a/mod_auth_mellon.conf b/mod_auth_mellon.conf
index 28b8bf705cf6d41eb7725d2b1823ef4b6fc63b6e..67b7dcc80be47cecf9c41083c89b56d93107ec2b 100644
--- a/mod_auth_mellon.conf
+++ b/mod_auth_mellon.conf
@@ -1,4 +1,5 @@
 ServerName https://{{HOST}}
+SetEnv HTTPS
 
 <Location / >
  MellonEnable info