What code page is being used now?
You can try using code page 65001 (utf-8), or 936 (gb2312), or 20936 (x-cp20936). There are other simplified Chinese code pages, too.
https://learn.microsoft.com/en-us/windows/win32/intl/code-page-identifiers
https://en.wikipedia.org/wiki/Code_page_936_(Microsoft_Windows)