Shock, if the NVR loses network, it won't be able to send me emails period, but not a bad idea to enable the health monitor. The guy called me from his house, and said he was able to go on the internet on his phone, but was getting time out and he was on his own wifi. I have been using nvrdns.com, and if anyone calls me with a connection issue, I just log into my own NVR to test
out nvrdns. Only once or twice, nvrdns was actually down, otherwise, I am very happy with them. I also have been using quickddns.com which is Dahua's new icloud
ddns service. You just register a username and enable it in the NVR, create your own name, enter your email, and in the iphone app, you click on quickddns, and it automatically finds your NVR. So, since the NVR has both choices, just to be safe, I enable both ddns services just in case one is down.