how to make one of my email addies the DEFAULT one

I'm using Windows Live Mail. I have six email addies. In Tools, Accounts, I set one as the "Default Account" and there it shows as such. BUT, if I happen to be looking at my emails in a different email account, and happen to start a new email, then the "From" address does NOT show the DEFAULT one; it shows the addy matching the email account I happen to be in.

How can I really make one the Default address so that ALL new emails, no matter what account I happen to be in, come from that one, same, default adddress?

Hope that makes sense............ it does to me........

I dunno. Even in Outlook 2007, when replying to an email that was sent to an address other than the default one, it is necessary to manually change the "from" email in order to reply from the default email address.