I received a new Dahua NVR4208 from Nelly's Security. This is my second Dahua NVR since I returned the first one (not from Nelly's) because it wouldn't record. I was able to change all of the passwords, but found that I could only change the password of the account I was logged into. In other words, I was able to change the admin users password from the default "admin" but was prevented from changing the 888888 users password. When I logged in as user 888888, I was able to change its default password. I don't know if this is how it suppose to work, a glitch in the firmware, or ignorance on my part. However, I am posting this because it may help someone. Or, maybe someone can disabuse me of that ignorance.