MSI MS-7623 motherboard archive in rar format, 810 KB, whose name gives no hint of the document type. It could be a schematic, boardview or BIOS file; extract it to find out. MSI uses the MS- pattern for boards it designs, and the same number can cover several revisions, so look for the revision code silkscreened on the PCB. Such documents are used to trace power rails, check the VRM and locate components when diagnosing a dead board.
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 @schematicslaptop. 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.
7-ZipWinRARThe Unarchiver (macOS)