tiscali problem sending and adding account

[alanmalarkey]

I have a legacy tiscali email address which I use mainly for joining accounts and other stuff - I generally receive my emails via a client such as thunderbird and Mail on mac and I can access and send emails via the talk talk mail feature. However I cannot send mail out from this address via the client and having just reinstalled an erased hard disc on my Imac I find I cannot aggregate the account into either Mail or Thunderbird. The Tiscali address stems from being my then service provider but I have long since moved to other providers and now am on BTinternet. This works fine on the Mail and Thunderbird clients as does a gmail address. The messages back on attempting to join the account are that the server isn't recognising mail address and/or password although access is fine via Talk Talk.
In Brief
Why can't I add the account to client services
why can't I send tiscali mail from clients where I have added the account for example other platforms?

[walesrob]

Here's the talktalk help page with settings for Tiscali (and Pipex, Lineone, Screaming.net, Blueyonder, ntlworld if anyone is interested):

http://m.help.talktalk.co.uk/email-settings-imap-pop3

My Pipex DSL email account is still active and the POP and SMTP servers are valid, so I'm guessing TalkTalk must have done the same with Tiscali.

[alanmalarkey]

many thanks

[gj15]

Originally Posted by alanmalarkey

However I cannot send mail out from this address via the client

Originally Posted by alanmalarkey

now am on BTinternet

It is fairly standard practice in the UK that an ISP won't let you use their SMTP server for sending mail unless you are connecting to it from within their network. From BT, you are now outside the TalkTalk network and it will be TalkTalk's policy to simply not let you connect and send mail no matter what your attempts to authenticate may be. Using their webmail service makes you appear to be within their network hence there is no problem sending mail by this method. Collecting mail by client never seems to be an issue though.

Originally Posted by alanmalarkey

I cannot aggregate the account into either Mail or Thunderbird

You will need to bypass these mail client's desires to automatically configure the account. Use a manual configuration to set up a collection method (IMAP / POP) but don't register an SMTP server.