Dear Taco, Thank you for your comment. I renamed the font to ~.ttf, luatools --generate first. And try the same file. At this time, there is no "Fatal error messages", but still it doesn't locate the font file. So, I tested a few more things. Test 1: luatools locates all the fonts which has no space from the same font maker. And, LuaTeX runs well to yield fine output. Math-iMac:~ graph$ luatools 산돌돌CB.otf /Users/graph/Library/Fonts/산돌돌CB.otf Math-iMac:~ graph$ luatools 산돌명조B.otf /Users/graph/Library/Fonts/산돌명조B.otf ####### Test 2: luatools cannot locate the fonts which has space from the same font maker. Math-iMac:~ graph$ luatools 산돌명조M.otf Math-iMac:~ graph$ luatools 산돌명조 M.otf Math-iMac:~ graph$ luatools 산돌명조\space M.otf But it locates the same file if I enclose "font name". Math-iMac:~ graph$ luatools "산돌명조 M.otf" /Users/graph/Library/Fonts/산돌명조 M.otf So I tired \definefont[testfont][file:"산돌명조 M.otf"], but LuaTeX issue an error system > begin file testmp.tex at line 29 ! LuaTeX error <main ctx instance>:1: ')' expected near '?'. system > tex > error on line 30 in file testmp.tex: LuaTeX error ... 25 26 \definefont[testfont][file:"산돌명조 M.otf"] 27 28 29 \starttext 30 >> \testfont 31 \chapter{X} 32 \section{One} 33 \dorecurse{10}{test fone file. } 34 \dorecurse{10}{산 돌 명조 폰트 file입니다. } 35 36 \stoptext \lowleveldefinefont ...ies ", "\@@fontgoodies " )} \edef \somefontspec {at \n... \dododefinefont ...inefont {#2}\rawfontidentifier \csname \rawfontidentifier... l.30 \testfont ? I tested english font which has a space in its name and got the same results. For example, "Geogia Bold.ttf" font. luatools cannot locate it and LuaTeX said "unknown font." and used default font. I renamed it GeogiaBold.ttf in /Library/fonts and tried again, but not succeed. Hence, I think that the font whose name contains no space has no problem. The fonts whose name contains a space make a trouble eventhough I removed the space from it. Am I doing right? I am using Mac OSX. And, This is LuaTeX, Version beta-0.65.0-2010121316 \write18 enabled. (testmp.tex ConTeXt ver: 2011.02.25 22:03 MKIV fmt: 2011.3.1 int: english/english Thank you again. Best regards, Dalyoung