Use a tool like the Super Password Generator or a specific Excel-based calculator to find a temporary daily password.
Using default login passwords can expose H.264 DVR systems to security risks, including: h.264 dvr login password
On some models (like Lorex or older Hikvision), this hard reset will also erase your camera configuration and schedule. Take a photo of your wiring before proceeding. Use a tool like the Super Password Generator
If software defaults fail, you may need to manually reset the device to factory settings: h.264 dvr login password
Once you are logged in, securing your system should be your first action. Here is the generic path (varies slightly by manufacturer):