Torquil Macdonald Sørensen wrote: > I cannot get "PDF (xetex)" output from the attached document which uses the > Theorems module. I'm using LyX 2.0.2 and Debian Sid with texlive-xetex. It > works fine when not using Theorems. > > The error I get is: > > "! Undefined control sequence. > \definitionname ->\inputencoding > {latin9}Definition
Yes, that's a known bug: http://www.lyx.org/trac/ticket/7800 A crude workaround is to put \providecommand\inputencoding[1]{} in your preamble. HTH Jürgen