diff --git a/src/routes/mailserver.js b/src/routes/mailserver.js
index c51e46e25..a70993e9f 100644
--- a/src/routes/mailserver.js
+++ b/src/routes/mailserver.js
@@ -20,8 +20,9 @@ const assert = require('assert'),
     services = require('../services.js'),
     url = require('url');
 
-function restart(req, res, next) {
-    mail.restartMail((error) => debug('Error restarting mail container', error));
+// because of how the proxy middleware works, the http response is already sent by the time this function is called
+async function restart(req, res, next) {
+    await safe(mail.restartMail(), { debug });
     next();
 }