Boardview archive for the Dell mainboard numbered 13321-1, a Wistron design, weighing 14.2 MB as a zip. Unpacked, it gives a component placement map with net names so you can locate test points, identify parts near a short and follow a signal across layers. Formats like this open in OpenBoardView, FlexBV or BoardViewer depending on the file inside. Use it together with the 13321-1 schematic, and verify the Wistron board number on the PCB because Dell models often share chassis across different boards.
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.