UPDATE: I installed the firmware specifically for this issue here (K71) and the issue is now fixed
After upgrading to the latest firmware from the DVR's page on hikvisions site here (V4.25.001 build 201107) and using the machine for a week I've been getting an error saying No more user can be connected. The error makes the machine go offline for local devices on hik connect and IVMS 4200 and the password on the DVR stops working and the only solution is to reboot via IP or unplugging because this clears the online users list. The online user list sometimes doesn't clear users after they have accessed the machine locally so when it gets to 128 online users the error occurs.
I've found this firmware which looks to be specifically for this issue and I think my machine is K71 here
And this firmware which is the latest one I could find on the portal here
I'm obviously leaning towards the firmware specifically for my issue but before I install it I would really appreciate some confirmation from other people that this firmware is for my DVR (DS-7208HTHI-K2) because I dont want to mess anything up. Any replies are greatly appreciated.