Yesterday I attempted to send mail to multiple recipients. Error message below received. Tried with fewer recipients - still rejected. Now all emails, even sent to single address, are errore with the same message.
The message could not be sent. The setting for your outgoing email [SMTP] server might need to be configured. To find the server settings for '######@######.com', please contact your email service provider.
Server Error: 453
Server Response: 453 4.1.1 NwdsjfQz1ltwL Too Many Recipients (TT502)
Windows Live Mail Error ID: 0x800CCC79
Please sign in to TalkTalk Mail using your tiscali email address and password. Tell us if there's an error message or if you can sign in ok. And then compose and send the same email address a mail message to prove that the message is seen in the Sent objects folder and in the Inbox.
However, you may need to wait until tomorrow for the sending limit counter to be fully reset.
Your Windows Live Mail (WLM) email client is not using secure settings. It is required that secure settings are used and your outgoing mail is authenticated by the network to ensure mail is accepted by recipients.
The recommended settings are Email settings - IMAP & POP3
But WLM is outdated and you'd be best to consider Windows Mail or Thunderbird, for example.
Advice on using TalkTalk Mail.