Openbox S3 firmware build v1.12 dated 15 June 2016, in a 6.92 MB ZIP, roughly double the size of other S3 packages, which suggests extra files or several images inside. Unpack it and review the contents before flashing. Such software is used to reload a receiver with boot or menu faults, or to return to this specific release. Confirm the unit is the S3 model, keep a copy of the channel list, and use stable power plus a known-good USB drive or serial lead while the update is written.
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.