Windows Live Messenger won't allow sign in on other e-mails

[Hockeyboy08]

Hey there. I am using Windows Live Messenger 8.1 on a Windows XP Home Edition with SP2 installed. My web browers are Internet Explorer 7 and MSN Explorer.

This is actually not my computer but my parents/little sister. My mother and younger sister both use the same Windows Live Messenger program but diffrent e-mails.

My sister has had a problem as when she tries to sign in on her own e-mail, it redirects her e-mail she typed in and the password to my mothers therefore signing into my mom's account instead of my little sisters.

I've tried a few things, logging out, clicking ''forget me'' and etc, but it doesn't seem to work. WLM keeps signing in on the same e-mail as I have tried signing on into my own e-mail as well. Does anybody have any solutions or suggestions I could try please?

Thanks in advance.