Tom_O

Paul - The first assumption is that Bosch has setup their own DDNS (dynamic DNS) server inside the DVR/NVR to discover and send out your home/building dynamic IP address from your service provider. If not, you will not be able to access your DVR/NVR from a mobile 4G/5G device. Hopefully, you are familiar with that concept. And, if that is all complete, then the other suspect would simply be a firmware issue with the DVR/NVR. On the Bosch support site, they note an issue with their mobile app's connectivity, to the 3000. Here is that link > https://community.boschsecurity.com/t5/Security-Video/DIVAR-Mobile-Viewer-v3-1-0-app-fails-to-connect-to-DIVAR-AN/ta-p/11116 . Just be sure to do backups of all your settings prior to upgrading firmware; sometimes it is also worth writing them down, as some backups will not restore once the firmware has been upgraded (compatibility issues). Hopefully, Bosch is better than that. Also, Bosch notes there could be additional problems if the mobile app is trying to view too many cameras as the app starts. Here is their statement: "For the DIVAR AN 3000/5000 we just learned that the DIVAR Mobile Viewer app v3.1.1. can consume more than one session per device. This typically happens when in the Live Preview the "Device List" (top right icon) is used to open all cameras simultaneously. This seems only to happen as a first action when you open the app. This can result is a failing connection showing the message “System is busy”. For the moment please apply these workarounds avoiding this connection problem: - Change the number of remote sessions allowed (default=4) in the DIVAR AN 3000/5000 configuration to 64 (Menu, Settings, Network, Max. connection) OR - Avoid the use of "Start Live Preview (16)" in "Device List" as an first action. By viewing one camera only as first action showed that new session consumption was prevented.