A reference document (board LA-C621P, LA-C631P). Shared as “LA-C621P_LA-C631P报错解决方法.txt” — a .txt file, 424 B.
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 @ShareMan_Electronic_Files. Enginerys does not host this file.