Firmware downloads usually come as a .zip or .tar file. You must extract it to find the digicap.dav file, which is the actual update file.
The DS-2CD1021-I has several hardware sub-variants. Before downloading, check the label on the camera or the device web interface (System > System Settings) for these specific suffixes: Standard DS-2CD1021-I : Often uses the firmware series. DS-2CD1021-I(D) : A specific hardware revision. DS-2CD1021-I(E) ds2cd1021i firmware download better
The firmware file for the DS2CD1021-I typically has a filename like: Firmware downloads usually come as a
: Download the firmware zip file and extract it to find the digicap.dav file. never over unstable Wi-Fi.
Always perform the update over a wired Ethernet connection , never over unstable Wi-Fi.