|Sounds like the dvr is looking for authenication and since its not getting it its shutting down the connection.|
What are you using to access the dvr? The dvr software?
Gretti forgot to tell you if you want to change the port you need to change the listener which is the dvr. You would change the port being listed to in the dvr network setup.
Then you would forward that port in the router to the static ip of the dvr.
You would want to go to portfoward.com or shields up! and do a port test on the port number you selected to make sure your changes were successful.
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