Outlook 2010 displaying accented fonts

I have a user that, sporadically without pattern, writes either a new email or replies to an email. Outlook begins adding an accent mark between specific character combinations (st, ch, and ct).

I've tried to repair Outlook, repair Windows 7, uninstalled and reinstalled ALL Windows fonts, deleted FNTCACHE.dat from %systemroot%, double checked Stationary settings, and even replaced Normal.dotm and NormalEmail.dotm files.

It is an Exchange user, and the issue does not seem to be in her webmail account or mobile account. It's localized to her machine and installation, and not all recepients receive this tainted reply.

Thank you for any advice!