If your DS-2CD1043G0-I is locked because you forgot the administrator password and cannot contact the seller, Hikvision requires a specific (sometimes called "Reset to inactive" firmware). This is not the standard digicap.dav . Do not attempt to use standard firmware to bypass security; you must use the official Hikvision password reset tool or contact an authorized integrator.
Extract the downloaded file. Inside, you will typically find a file ending in .dig or .dav . This is the actual firmware file. Do not try to upload the .zip folder itself. ds-2cd1043g0-i firmware download