OK... I have encountered the most bizzarre thing:

My client's computer will not log into Hotmail with her Hotmail account. I can log into my Hotmail account on her computer. And I can log into her Hotmail account on my computer!

I have cleared cookies, history, Temporary Internet Files, reset Internet Explorer settings... still no go.

After you click to sign in with her account it goes to a loading screen and just sits there. It seems to load her account ok through Hotmail section of the MSN Today window in MSN Messenger.

Any ideas ?