Hi, For this example with simsun.ttc (it can be download from http://www.slax.org/modules.php?action=detail&id=2630): \definefont[song][name:nsimsun] \starttext \song 测试 \stoptext ConTeXt MkIV said: fonts > fallback modern rm 12pt is loaded system > begin file b at line 3 fonts > otf loading > loading: selfautoparent:texmf-local/fonts/truetype/winfonts/simsun.ttc (hash: simsun-nsimsun) fonts > otf loading > font loaded okay fonts > otf loading > loading failed (file read error) fonts > defining > forced type ttc of simsun not found I have tested the uming.ttc (AR PL UMing, it can be download from http://www.freedesktop.org/wiki/Software/CJKUnifonts/Download) and got the same error. -- Best regards, Li Yanrui