Apparently TalkTalk mail will work with Firefox 4 and Firefox 5 ''if'' you set the browser to ''lie'' to TalkTalk mail by saying that you are still using version 3.6. You can find the instructions for that in a post on the TalkTalk forums: [http://www.talktalk.co.uk/forums/showthread.php?t=185113#post2452787 Firefox 4 & TalkTalk webmail - Forums]. Note: when you open about:config the first time, it will display a warning message that you should be careful with the changes you make. That's definitely good to bear in mind. Does it work?