Not using Xp or Outlook but I imagine it's to do with Internet Explorer and Outlook 2003 not being default. Most probably you've got another browser that is set as default. Have a look at your settings, from memory it's something like, start, then on the right hand side you should have something like default programs. Hope that helps.
The Legend of Zelda Breath of the Wild review: Five hours with Zelda on the Nintendo Switch