I get the following error message on MacOS X Mavericks /usr/local/texlive/2014/texmf-dist/tex/latex/newtx/omlnxlmi.fd:16 Undefined control sequence. l. 16 \iftx at liby If I back out from TexLive-2014 to TexLive-2013, the error goes away. Fortunately that is easy on MacOSX.