How do I eliminate the unnecessary WLM sign-in pop-ups?

I'm somewhat new to WLM. When coming from a previous XP, EI8 computer, I transferred my internet settings into my new Win7, EI9 program. WLM worked perfectly right from the beginning. A couple of days into my use of WLM, at some point I was presented with a sign in page, and I entered my email address and password, thinking that it was necessary. However, ever since then, whenever I hit the email icon in the bottom tray or "read email" in the command line of IE9, a sign-in pop-up appears every time, even though, behind it, WLM is already checking and downloading email. I just cancel the pop up each time, but it's an annoyance that I don't want to experience for ever! How do I remove that pop-up sign-in?

Would value help! Thanks!