> I'm thinking specifically about apps "Outlook Express,"[...] Fuhgeddaboutit. First and foremost, OE is proprietary code belonging to a small company you might have heard about, called Microsoft. Modify it or use the code in any way, and you'll have ten packs of legal wolves howling for your blood -- with a cistern of piranhas lining up behind them. Second, "carbonizing" a major app like OE is a seriously non-trivial task. If you want to learn Carbon, that's not what you should start with. Third, free e-mail clients do exist. Mail.app is part of OS X; and if that's not good enough for you, try pine. f Thanks for the information and advice. I use "Mail" myself and like it just fine. But others may not. Although Microsoft does own Outlook, it is a free download to use on your computer. Are you saying that legally a person is not allowed to add something to it to make it run properly? Maybe, but that is just an example. Thanks again, Anand