Locally (on the same LAN):
Install SADP on your PC, use it to scan your network - note the NVR's IP address.
Use the internet Explorer browser.
Enter the NVR's IP address in the address bar of IE.
You should be able to login, view, replay, config. etc.
To access your NVR from a browser at another site:
You will need to configure port forwarding on the router at the NVR site.
Also, if the NVR site does not have a static IP address, you will need to use a DNS service such us No-IP to be able to find the site and the NVR on the world wide web when your ISP changes the site's IP address.