Compressed RAR package named Z97-A, matching a desktop motherboard model built around the Z97 chipset. The name does not say whether it holds a boardview, a schematic or firmware, so extract it first to find out. At 477 KB it is more likely a layout or diagram file than a full BIOS image. Boardview layouts open in viewers such as OpenBoardView or FlexBV and help locate parts and test points. Always compare the revision silkscreened on the PCB with the document before using it for diagnosis.
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 @boardview. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.