: Some older "generic" H.264 units can be reset by removing the CMOS battery (small silver coin battery) from the motherboard for several minutes, which may reset the system clock and credentials. JustAnswer Brand-Specific Defaults Default Username Default Password (blank) or 123456 111111 or 888888 H.264 Default Password - Google Groups
If you are locked out, "Super Passwords" are often generated based on the system date shown on the DVR screen. Date-Based Generators: h.264 dvr login password