V4.30.120 Build200630 - 2021-05-03
V4.25.000 build200925 - 2021-04-12
V4.21.100 build 200307 - 2020-06-15 V4.20.001 build 190430 - 2019-09-20- I have this one installed and it runs OK
Witch one I can use for my DS-7104HQHI-K1(B) - K72A - DVR?
We don't have much hands-on experience with DVRs and analog products, so we would probably just suggest that you update one firmware step at a time and then if the install is successful you should check all the settings/menus that you regularly use to make sure you haven't lost any functionality, before then stepping up to the next firmware.