I've recently installed IE8 on Windows XP Professional SP3, and am
encountering a compatibility problem between Outlook Express and IE8 that I
never had with IE7.

When the IE8 window is in focus, pressing the e-mail key on my Microsoft
Wired Keyboard 500 does nothing. If I minimize IE8, or if I open another app
and give its window focus, the e-mail key will start Outlook Express.
Basically, Outlook Express will only start when an IE8 window is not in focus.

Also, the Read Mail button on IE8's Command Bar does not start Outlook
Express, even though under Internet Options > Programs both E-mail and
Newsgroups are set to Outlook Express.