Always read the PDF release notes included with the download to see if a "bridge" firmware is required before jumping to the latest version.
Never turn off the NVR or disconnect the network during the update process.
This is the primary source for the latest "K Series" NVR firmware. Hikvision Download Center
Once you have downloaded the .dav firmware file, follow these steps: Method 1: Via Web Browser (Recommended) Connect your PC to the same network as the NVR. Enter the NVR's IP address into your browser and log in. Navigate to > System > Maintenance .
Note the exactly (e.g., DS-7616NI-K2 vs. DS-7616NI-K2/16P). Step-by-Step Update Guide
Copy the digicap.dav file to the root directory of a FAT32-formatted USB drive. Plug the drive into the NVR’s USB port. On the local monitor, go to > Upgrade . Select the file from the USB and confirm. Important Safety Tips
Avoid updating over Wi-Fi, as a signal drop can corrupt the installation.