Having the very same problem as JillaWright, and seeing the one  the reply I thought my problem at last could be resolved. WRONG!

After duly going through the steps ie telephoning the UK number as given and then after 14 minutes at £0:14 / min only to be told they could not locate my account (which I have had for some 8 years) and I should then contact Support@Microsoft to assist.

Having then gone down this route to no avail. I am now resolved to the fact that the Customer Service from Microsoft is abysmal and it would be better to find another provider.  

My wifes credit card was out of date when the billing date came for Outlook. I have wasted hours trying to change the billing details for her. Paypal did not work so I added another credit card, which the system recognises, but does not allow me to activate. Seems to me brain numbing incredible that it is impossible to contact Microsoft on these matters even when you want to pay them money!!!!!!!!!!

Has anyone got any ideas how to proceed, or should I just give up on ad-free hotmail/outlook?