[XeTeX] problem with package versions?

[Will Robertson]

On 2010-11-15 10:18:56 +1030, Adam McCollum 
<acmccollum101 at gmail.com> said:

> When I run XeLaTeX on a file (I've tried several), I get this error
> message.
> [snip]
> By the way, I've run TeX Live and updated everything.

You must be using TeX Live 2009. The current version is TeX Live 2010, 
and you can't upgrade from the former to the latter -- it must be 
installed fresh (multiple distributions happily live in parallel, 
though).

Another alternative is that you have an old version of fontspec 
installed in your local texmf tree.

Cheers,
Will