QNAP 4.3.5.0760 problem

[simoncn]

Did you check that the MinimServer status web page is shown when you click Open? Sometimes the App Center icon stays green when MinimServer is not running.

If the status page is shown, there might be a firewall or security program on the NAS blocking UPnP access to MinimServer. Another possibility is a multicast discovery problem with your network. See this page for more information and some suggestions.