diff --git a/adjuster.py b/adjuster.py
index b6ef7ae90b4f25d6ee7d9b0f11a05a0d4afb8194..6cb0bd84c8d12a4d70347e6a7f1b247984007947 100755
--- a/adjuster.py
+++ b/adjuster.py
@@ -1575,7 +1575,9 @@ document.forms[0].i.focus()
                   elif maybeRobots: return self.serveRobots()
                   else: options.auth_error = "auth_error set incorrectly (own_server not set)" # see auth_error help (TODO: is it really a good idea to say this HERE?)
               elif maybeRobots: return self.serveRobots()
-              elif options.auth_error.startswith("http://") or options.auth_error.startswith("https://"): return self.redirect(options.auth_error)
+              elif options.auth_error.startswith("http://") or options.auth_error.startswith("https://"):
+                  self.add_nocache_headers() # in case they try the exact same request again after authenticating
+                  return self.redirect(options.auth_error)
               if options.auth_error.startswith("*"): auth_error = options.auth_error[1:]
               else:
                   self.set_status(401)