If later encountered "Unable to connect to ' down.xyzs.com '" first check whether there is a network, if there is no network, or only attached to the LAN, then you do not have to look down oh.
1: Exit the background, exit the process, reopen the assistant to try to download. (if not, then make sure it is a network problem, try the next one).
2: Exit the app, set-Universal-date and time to auto-set (if it's already automatic, turn it off on. ) and enter the application again.
3: If you still can not download, and you are WiFi environment, then trouble you restart your router, then do not worry, wait for 10 minutes and then restart the route, if it is cellular network, then the original network settings, and then wait 10 minutes.
4: This is a big move, can go to this step to show you very unfortunate (probability is very low) Oh, but if successful is lucky. After successful, please change the DNS of WiFi back in time.
(1) Exit the application process.
(2) WiFi found current connection network-dns changed to 8.8.8.8 or 8.8.4.4 or 114.114.114.114.
(3) Open the app and try the download again.