Compact 233 KB zip whose name indicates a boardview (BVD) for the Toshiba board coded TRKU, though the name gives no model or revision. Boardview files show component placement, part references and net connections on both sides of the PCB, letting a technician find test points, trace a signal to a pin or locate a shorted capacitor quickly. Such files open in tools like OpenBoardView or FlexBV depending on the format inside. Confirm the TRKU code printed on the motherboard before relying on it.
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 .zip file
Compressed archive that every operating system opens without extra software.