Archive of 4.13 MB named HPC-S-MV-MB-V3, where MB most likely refers to a motherboard and V3 to a version or revision. The name does not state the device brand, model or whether the contents are a schematic, boardview or firmware, so treat it as unidentified until opened. Technicians typically use such packages to follow power rails, check signal paths and find test points. Confirm that the version printed on the actual PCB matches V3 before trusting component values or connector pinouts inside.
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 @ITHINKHS. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.