Thank you. I had never heard of "luatex/mkiv format" before---I have just been trying to follow the four or five conflicting pages about installation that I found at Context Garden. I did a Google search there for "luatex format", which does not occur, and for "mkiv format", which occurs once, under a heading about updating existing installations. It says: * For making MKIV format luatools --selfupdate mtxrun --selfupdate luatools --generate context --make I tried these commands and, indeed they ran. I also changed my command line to: context --interface=en --language=en test.tex I had been trying to follow the example on the Context Garden page, which contained the incorrect command and flags you saw. Now when I run context, I get less promising output than before: MTXrun | run 1: luatex --fmt="C:contextminimal/tex/texmf-cache/luatex-cache/context/d1d2ccfb3346ff481f4c4dab022cb26d/fomats/cont-en" --lua="C:contextminimal/tex/texmf-cache/luatex-cache/context/d1d2ccfb3346ff481f4c4dab022cb26d/fomats/cont-en.lui" --backen MTXrun | fatal error: no return code, message: luatex: No such file or directory