The chat lady in India said that my password was 'invalid' and she has re-set it. Why it suddenly became invalid, who knows, as I've been using it for months. I can recommend the chatline on the help section of BT's website; very quick and efficient! Of course, if your broadband has gone down it's not available.
Dell Studio1558 with Win7 Home Premium 64bit 8GB RAM
IE9 and Live Mail
BT Infinity via HH3