diff --git a/example/calculator-aserver.cpp b/example/calculator-aserver.cpp
index 536ee25..290e0aa 100644
--- a/example/calculator-aserver.cpp
+++ b/example/calculator-aserver.cpp
@@ -13,21 +13,23 @@
         ctx.spawn(startup());
     }
 
-    auto get_property(owner_t) const
-    {
-        return "asdf";
-    }
-
     auto get_property(last_result_t) const
     {
         return 42;
     }
 
+    bool set_property(last_result_t, auto)
+    {
+        return false;
+    }
+
   private:
     auto startup() -> sdbusplus::async::task<>
     {
         ctx.get_bus().request_name("net.poettering.Calculator");
 
+        status(State::Error);
+
         while (1)
         {
             using namespace std::literals;