Archive of 334 KB for Quanta board DAX12AMB6D0, revision D, packed as ZIP. In Quanta numbering the D near the end of the code matches the stated revision. The small size suggests a boardview or firmware image rather than a complete schematic. Boardviews open in OpenBoardView or FlexBV for locating components and test points, while firmware should only be written after backing up the original chip and confirming the image size matches the flash capacity.
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 @ITHINKHS. 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