I suspect I may have rebooted the NVR before the flash finished. It said finished on the
TFTP screen, but......
There are 3 main steps that take several minutes, after the file has been transferred.
Erase flash, write flash, check flash.
Then the reboot.
It cant do anythign with the TFTP device, and even connected to a moniter = nothing. No beeping at all when I turn on. Just nothing.
That does not sound promising. You may have to resort to a connection to the serial console, via the main board connector, for recovery steps.
A suggestion to check for any remaining activity:
With PC and NVR both wired (no WiFi) to your router or switch as normal.
Set the PC IP address to 192.0.0.128
At a command prompt, use 'ping -t 192.0.0.64'
Power cycle the NVR.
Check for ping responses.
2 or 3 after a few seconds, with no repeats is normal, and suggests the bootloader is active and checking for a tftp server.