 <blockquote> <p>On my workstation, Vim and the Vim syntax file are versions 7.3 and 0.93 respectively, while on my server 7.2 and 0.88.</p> </blockquote> <p>That explains it. The <code>'colorcolumn</code>' was introduced in Vim 7.3. Your <code>~/.vimrc</code> has a fallback using <code>matchadd()</code> for older versions, but that one only highlights actual occurrences that exceed the width, not a continuous line.</p> <p>The different Vim versions ship with different syntax scripts, in <code>$VIMRUNTIME/syntax/fortran.vim</code>. Updating Vim will automatically get you a corresponding newer version of the syntax script, as it's part of the runtime.</p> <p>For custom syntax scripts (that you've downloaded somewhere, e.g. from <a href="http://www.vim.org/" rel="nofollow">vim.org</a>), or to get the latest and greatest of the Fortran syntax (my Vim version 7.4.716 has version 0.95 from 2015 Jan. 15), you'd have to download a new one and place it into <code>~/.vim/syntax/</code>, where it would override the runtime one. (But then you have to maintain that copy yourself in case of Vim updates.)</p>