The Office 2007 proofing tools do not support MS Outlook Express (part of Internet Explorer).
You can do a custom install of an older version of Office for just the proofing tools (but that can be problematic later in needing
to update things) or you can add a 3rd party speller for Outlook Express.
A couple of free ones that folks have mentioned include.
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.