I am trying to send some photos from my desktop win7 computer with windows live mail.  I open live mail, select Photo Email and a pop up windows displays that says "Sign In To Windows Live Mail".  I'm in my windows live mail program on my computer.  Why and how do I need to sign in again.  Can someone please give me a step by step on how I can send someone several pictures from my computer that will arrive at the recipients email program with the option of viewing them as a slide show.  I know it can be done because my son has a Win7 computer and is using windows live mail and has sent me photos that give me the option of viewing them as a slide show.

Thank you for your help.

Mac