Outlook Express Question

My inlaws use Outlook Express 6 as their email client. It works well, except
that when they print an email, the HTML codes appear in the printout. (HTML
codes also appear in the Outlook Express help screens.)

I am aware that Outlook Express printing is controlled by Internet Explorer,
but cannot find any relevant settings there. I am also aware that this
problem can arise when the .TMP extension is mistakenly set as the default
for an application, but that is not the case here.

Can anyone help?