I also tried using these cmd commands
ipconfig/release to release old IP address
ipconfig/renew to get new ip address
...but it didn't work. It just resulted in having the same IP address, and username admin, password admin didn't work.
In order to use the Blue Iris mobile app, I'm planning to use my PC as a server to store and access IP camera footage. I have my PC's LAN internal IP address: 192.168.x.x:x, (including port), but I don't know that IP address (and port)'s username and password. I never needed it until trying...