How can I contact Windows Live Messenger about a problem I am having with a contact?

I have tried looking and have only found their support page and no email address on it.

The problem I am having is that my friend cannot see me on messenger, and only recently she cannot see my messages when I send them. She doesn’t have me blocked and we have already tried reinstalling both of our messengers (although I use pidgin). We used to be able to talk previously without hassle.

Thanks