diff --git a/cloudron.js b/cloudron.js
index 957395e..e3cf614 100644
--- a/cloudron.js
+++ b/cloudron.js
@@ -178,7 +178,7 @@ Cloudron.prototype.uninstallApp = function (appId) {
         }
     }
     debug('App is uninstalled'.green);
-}
+};
 
 Cloudron.prototype.update = function (toVersion) {
     process.stdout.write('Trying to update');
@@ -188,6 +188,7 @@ Cloudron.prototype.update = function (toVersion) {
         process.stdout.write('.');
         res = request.post(this._origin + '/api/v1/cloudron/update').query({ access_token: this._credentials.accessToken }).send({ password: this._credentials.password }).end();
         if (res.statusCode === 422) continue; // box has not seen the update yet
+        if (res.statusCode === 409) break; // update is in progress, lock was acquired
         verifyResponse(res, 'Could not update');
         break;
     }