It has some camera that are compatible only with the dvr / hvr of the same factory, it has own communication protocol. The ONVIF protocol camera is usually compatible with almost all HVR / NVR, unless the Manufacturer does not place the ONVIF protocol on their HVR / NVR.
To know the Model of your DVR/HVR, save the in Advance / Import Export / Config Export Will generate the file Cfg_V4.02.R11.00000117.10001_201611191129.cfg rename it from cfg to zip, open it and look inside the ProductType.ini will contain the PCB model Example: AHB7004T-EL (in this example, firmware 00000081 and 00000117 Is compatible with this DVR/HVR
Firmware Download
http://www.hkvstar.com/technology-news/china-dvr-nvr-firmware-download.html
Firmware DVR/HVR
Firmware PCB 00000114 (AHB7804T-EL) is Compatible with Models:
AHB7804T-EL
AHB7808T-EL
AHB7804T-LM
AHB7804R-EL
AHB7808R-EL
AHB7804R-LM
Firmware PCB 00000081 (MBD6304T) is compatible with Models:
MBD6304T-EL
MBD6304T-H
MBD6308T-EL
MBD6004Q-E
MBD6004Q-H
MBD6008Q-EL
Firmware PCB 00000117 (AHB7004T-EL) is compatible with Models:
MBD6508T-H
MBD6516T-EL
MBD6508H-H
MBD6608H-H
MBD6508V-H
MBD6516H-EL
MBD6616H-EL
MBD6505E-PH
MBD6505H-PH
MBD6605H-PH
MBD6509E-PEL
MBD6509H-PEL
MBD6609H-PEL
AHB7008T-LM
Firmware PCB 00000115 (AHB7008T-LM) is Compatible with Models:
MBD6508T-H
MBD6516T-EL
MBD6508H-H
MBD6608H-H
MBD6508V-H
MBD6516H-EL
MBD6616H-EL
MBD6505E-PH
MBD6505H-PH
MBD6605H-PH
MBD6509E-PEL
MBD6509H-PEL
MBD6609H-PEL
AHB7008T-LM
I made a step by step video for DVR recovery if DVR Blink follow link
See in resolution 720p
Good luck.
by Idelson - Brazil