Dell Latitude 5480 and 5488 package, 3.87 MB RAR, for Compal boards LA-E082P and LA-E081P at Rev 1.0, platform code CDM70. The file type is not specified, but this size usually means a schematic or boardview set. Use it to follow power rails, check signal routing and locate components and test points during repair. Compal numbers its designs LA-xxxxP, and since two variants are listed, check which one is printed on your PCB along with its revision.
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 @SCHEMATICWORLD. 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)