“Send Link by Email” Problem

I’ve got an XP client that keeps trying to use MS Outlook and Exchange when attempting to send a link in Internet Explorer by email.

I’ve got the default email client in IE set to Outlook Express which is what I want it to use but every time we try to mail a web page or link it pops up a window for us to choose a profile in Exchange.

How can I get this thing to use Outlook Express?