Server '127.0.0.1 is a local host, usually put there by anti-virus software, not the real server name at NTL.
I remember ME having this problem recurringly, particularly with Trend AV software. There never did seem to be a real cure - the problem doesn't seem to occur with XP (or maybe the AV vendors have got themselves more sorted now.
So - delete and redo your email account, with the correct NTL servers.
What AV software are you using? You may have to rest it to be active on your email again.