Very small 18.0 KB ZIP named T-840 with a string that likely encodes the date 12 December 2016, but the device type and brand are not stated. At this size it is probably a settings file, channel list or small configuration file rather than a full firmware image. Open it to check the contents and any readme before use. Confirm that the target device model matches, and keep a backup of the existing configuration in case the imported data needs to be reverted.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @tvsoftwareworld. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.
Built-in OS tools7-Zip