By default, gvim on my Windows machines just displays question marks, boxes, or garbled characters when I try to open files with Chinese text. The fix was rather simple:
- From the gettext project on SourceForge, get libiconv-1.9.1.bin.woe32.zip, which contains bin/iconv.dll. Put that file into gvim's installation directory (for me, it's C:Program Files (x86)Vimvim73).
- Put this into vimrc:
set encoding=utf8 set guifontwide=NSimSun
Note: I'm using gvim 7.3.46 from the official site.
Credit goes to user Tobbe for this answer on superuser.com, which pointed out the key ingredient (iconv.dll).