diff --git a/src/mergerfs_webui.cpp b/src/mergerfs_webui.cpp
index c97a9280..6e0d8a64 100644
--- a/src/mergerfs_webui.cpp
+++ b/src/mergerfs_webui.cpp
@@ -358,12 +358,12 @@ _post_kvs_key(const httplib::Request &req_,
       if(rv >= 0)
         {
           res_.status = 200;
-          j["result"] = "success";
+          j["result"] = (json)"success";
         }
       else
         {
           res_.status = 400;
-          j["result"] = "error";
+          j["result"] = (json)"error";
           //          j["error"] = ::_generate_error(mount,key,val,rv);
         }