Dahua DHI-NVR4108-8P-4KS2 Can't do Factory mode / Reset

[andrewy]

How old is this NVR? If its from 2017 or later it may have a default password.
Dahua stopped using default passwords on firmware after 2017 due to it being a security vulnerability, so its worth a try.
Username: admin Password: admin
Username: 888888 Password: 888888

There is also the Dahua Password Generator, again only works on older models:

Download Dahua Password Generator (2024 Version) — SecurityCamCenter.com

This tool with generate a daily password that reset the Dahua master password. You just need to run the password generator and enter the actual DVR date to get a new password (the date you see on the screen).

securitycamcenter.com

Unfortunately if absolutely nothing from this forum works for you then the unit is done for which sucks,
but also the latest available firmware for this NVR is 2021 which is is 3 years old now.
DH_NVR4XXX-4KS2_MultiLang_V4.001.0000005.1.R.210713

Worst case scenario you can get an upgraded/newer replacement for $172, and it will have longer firmware support:

Dahua 12MP 8CH 8PoE 1HDD Smart 1U NVR NVR4108-8P-4KS3 4K Network Video Recorder | eBay

Dahua 8 CH Smart 1U 8PoE 1HDD NVR4108-8P-4KS3. Total output of NVR is <10 W(without HDD) Total output power of PoE is 72 W, the maximum output power of a single port is 25.5 W. > AI by Recorder supports 4-channel SMD Plus.

www.ebay.com