Great forum you have here, I have searched historic posts and have tried the suggested actions but I'm not getting anywhere (I'm not the best with these cameras).
I have had an 8 Hikvision camera setup for a few years, which has worked perfectly. The DVR connects to the IVMS 4200 desktop app and I use the IVMS 4500 iphone app. The only time there is ever a problem is if my external IP changes but I just go to the app, change it there and off we go.
A couple of days ago we changed to Vodafone Full Fibre Broadband and this is where the problem now lies. I can view the cameras on the desktop app but on the iphone app for each individual camera I am presented with the error [connection failed], I have the app pointed at the right port / the IP address is correct, along with the correct username and password. I don't see the option to change anything else.
In the desktop app under device management everything is ok, it shows that it is sending data externally, I just can't access it for some reason. If anyone can help that would be great! Thanks and Happy New Year to all!