I then checked the same link myself on my computer and had no problem sending the link to the article via File, Send Link. My Outlook Express pops up immediately, so that ruled out a problem with the link/article itself. I then tried it on her computer through Internet Explorer rather than Firefox to see if I got the same result. I was unable to send the link via Explorer as well. However, using Explorer I find that when click on File, then Send, the 'Link by e-mail' and Page by e-mail' options are not highlighted in black, but are grayed out. So they are not available to select in order to send the link via her Outlook Express.
It seems something is wrong with her Outlook Express, but what it is I don't know. She uses it everyday without a problem and I've checked it myself and found that I can send and receive e-mail through it without a hitch.
Any ideas what could be wrong?