diff --git a/etc/tinyproxy.conf.in b/etc/tinyproxy.conf.in
index 06f5480..ce27f7e 100644
--- a/etc/tinyproxy.conf.in
+++ b/etc/tinyproxy.conf.in
@@ -56,8 +56,8 @@ Timeout 600
 #   /usr/share/tinyproxy
 #   /etc/tinyproxy
 #
-#ErrorFile 404 "@pkgdatadir@/404.html"
 #ErrorFile 400 "@pkgdatadir@/400.html"
+#ErrorFile 502 "@pkgdatadir@/502.html"
 #ErrorFile 503 "@pkgdatadir@/503.html"
 #ErrorFile 403 "@pkgdatadir@/403.html"
 #ErrorFile 408 "@pkgdatadir@/408.html"
diff --git a/src/reqs.c b/src/reqs.c
index cdc3b61..50f6914 100644
--- a/src/reqs.c
+++ b/src/reqs.c
@@ -1424,7 +1424,7 @@ connect_to_upstream (struct conn_s *connptr, struct request_s *request)
                 log_message (LOG_WARNING,
                              "No upstream proxy defined for %s.",
                              request->host);
-                indicate_http_error (connptr, 404,
+                indicate_http_error (connptr, 502,
                                      "Unable to connect to upstream proxy.");
                 return -1;
         }
@@ -1436,7 +1436,7 @@ connect_to_upstream (struct conn_s *connptr, struct request_s *request)
         if (connptr->server_fd < 0) {
                 log_message (LOG_WARNING,
                              "Could not connect to upstream proxy.");
-                indicate_http_error (connptr, 404,
+                indicate_http_error (connptr, 502,
                                      "Unable to connect to upstream proxy",
                                      "detail",
                                      "A network error occurred while trying to "