I haven't had reason to send many emails recently, so I'm not sure how long this problem has been going on as I've only become aware of it in the last couple of days.
When attempting to send an email from my Tiscali account, my email client, Mac Mail, says it is unable to connect to the server. In Mail Preferences, the SMTP outgoing mail server (mail.tiscali.co.uk) is shown as being offline. I cannot use the smtp.talktalk.net server instead as it rejects my e-mail address, and I prefer not to use the webmail service. I have not made any alterations to any settings.
Thankfully, I have still been able to send my emails as I have accounts with other providers.
My incoming mail is not affected.
Thank you in anticipation of your help.....
JohnH999