Outlook

Following Lan's advice (when is that man going to get his Knighthood?) I have stopped trying to use outlook on the road, using webmail services instead. But I have another problem and I've been googling and can't seem to find the solution. Having changed from Outlook Express to Outlook, I am generally happy with it, but one thing has been bugging me. When I reply to someone who is not in my contacts list, sometimes outlook doesn't automatically give the e.mail and I have to search the e.mail to find it. This is a particular problem when I want to 'reply all' as many of the other recipients are simply named, with no e.mail given. Am I doing something wrong? It does seem strange that what OE did effortlessly, Outlook doesn't seem to be doing.

Thanks in advance