I also have this problem on my NX510v which is an ex-ISP model. The ISP won't help me upgrade the firmware so how do I do that? The options for Upgrade/Back/Restore/Factory Reset have been removed...

@ng6333 I'm in the same situation as @zaldasan: I bought a used NX510v from a second hand electronics store with a bunch of these for sale. It was factory reset and worked fine at first. But it drops...

I have a C225 V2 (EU) camera that failed to reboot after a power cut. When I unplug/replug it the red LED comes on and stays on. There is some clicking but that's it. I have tried resetting but...