Boardview for the ASUS H81M-D micro-ATX motherboard, revision 1.00W, stored in a zip of about 103 KB. The H81 chipset name indicates an Intel LGA1150 platform. Open the contents in a boardview program like OpenBoardView or FlexBV to see both board sides, search reference designators and follow nets while measuring rails or diagnosing a no-boot fault. The W suffix is part of the revision as given in the name; make sure the label on your PCB reads the same before trusting component positions.
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 @cynetitsolution. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.