Problem
You have received a dwg file that contains Japanese text, but it displays in non Kanji format. Adding the bigfont.shx, extfont.shx, extfont2.shx and @extfont2.shx fonts to the AutoCAD font directory does not solve the problem. Now that the fonts are present, the file still will not display correctly.

Cause
The DWG file was saved in a copy of AutoCAD that did not have the Asian fonts installed. As a result the DWG is corrupted because the codepage is now set to English (1252). Opening this same file in a correctly configured AutoCAD will still display the Asian fonts improperly.

Solution
you must download the repair utility shown in the link below, and use this utility to repair any damaged DWG files.

Steps to the Solution

Bigfont.ini file is needed when you have custom double-byte SHX fonts.  The following AutoCAD shipped Japanese double-byte SHX fonts don’t need be added to Bigfont.ini file: bigfont.shx, extfont.shx, extfont2.shx and @extfont2.shx.

• 10 Asian double-byte SHX fonts are included in all language version of AutoCAD 2007.  They should be installed to your Font folder of AutoCAD 2007 installed location.  If you cannot find them, it could be the font files were unchecked during installation.
• The problem of your attached drawing file is caused by the drawing has been saved with wrong codepage information - it was saved in English (1252) codepage (the same issue as Kanji.dxf file).  To fix this issue, please follow the steps as follows.

  a. Go to Autodesk Service and Support website:

  http://usa.autodesk.com/adsk/servlet/ps/dl/item?siteID=123112&id=8109007&linkID=9240618

  b.      Download “Modify Drawing Codepage Utility” – codepage_tool.exe and Readme file.

  c.       Follow the Installation Instructions in the Readme to install the utility.

  d.      Use this utility to modify the drawing codepage to Japanese (932).

  e.      The file should now open correctly.