diff --git a/boringproxy.go b/boringproxy.go
index efbf464..a8ec18d 100644
--- a/boringproxy.go
+++ b/boringproxy.go
@@ -299,7 +299,12 @@ func (p *BoringProxy) handleCreateTunnel(w http.ResponseWriter, r *http.Request)
 		return
 	}
 
-	p.tunMan.SetTunnel(host, port)
+	err = p.tunMan.SetTunnel(host, port)
+        if err != nil {
+		w.WriteHeader(400)
+                io.WriteString(w, "Failed to get cert. Ensure your domain is valid")
+		return
+        }
 
         http.Redirect(w, r, "/", 303)
 }
diff --git a/tunnel_manager.go b/tunnel_manager.go
index 6949d70..9e500a9 100644
--- a/tunnel_manager.go
+++ b/tunnel_manager.go
@@ -53,11 +53,11 @@ func NewTunnelManager(certConfig *certmagic.Config) *TunnelManager {
 	return &TunnelManager{tunnels, mutex, certConfig}
 }
 
-func (m *TunnelManager) SetTunnel(host string, port int) {
+func (m *TunnelManager) SetTunnel(host string, port int) error {
 	err := m.certConfig.ManageSync([]string{host})
 	if err != nil {
-		log.Println("CertMagic error")
 		log.Println(err)
+                return errors.New("Failed to get cert")
 	}
 
 	tunnel := &Tunnel{port}
@@ -65,6 +65,8 @@ func (m *TunnelManager) SetTunnel(host string, port int) {
 	m.tunnels[host] = tunnel
 	saveJson(m.tunnels, "tunnels.json")
 	m.mutex.Unlock()
+
+        return nil
 }
 
 func (m *TunnelManager) DeleteTunnel(host string) {