How do I set up smtp on Vista so I can use System.Net.Mail from local picup directory?

I've tried using the below solution (also found here: How do I set up smtp on Vista so I can use System.Net.Mail?) but I receive "Cannot get IIS pickup directory". I know I am pointing to an existing directory and my web.config are set up correctly, are there permissions I need to set up on the directory before I can write to it?

<system.net>
    <mailSettings>
            <smtp deliveryMethod="SpecifiedPickupDirectory">
                    <spe开发者_运维知识库cifiedPickupDirectory
                      pickupDirectoryLocation="c:\maildrop"/>
            </smtp>
    </mailSettings>

Have you checked the file permissions on the maildrop folder? You can enable write for all users and see if that works. If you just want IIS to write to it, I think the user is ASPNET, but I might be wrong on that.

Also this answer seems to show a "\" at the end of the directory path (I would hope asp.net would understand that though)