Windows Live Mail 2011 in Windows 7

Having just been dumped by Virgin onto Talk Talk (because we are non cable) all has been going well so far. Windows Live Mail 2011 allowed for emails to be sent to and from both Virgin and Talk Talk addresses, until yesterday. I am now, continually, getting a request for my password for the Virgin address. I have typed this in, but to no avail. It won't accept it. I am now in the position of being able to send and receive emails from Talk Talk, but only receiving into the Virgin address. I am unable to send anything from the Virgin address. I spoke to Virgin, who, on checking, said that this was a Microsoft problem. I had not had a problem, with Live Mail 2011, before this. Any ideas gratefully received.