Please, is there a solution to the following problem??

An unknown error has occurred.

Subject 'testing'

Server Error: 554

Server Response: 554 cm1nec smtp.talktalk.net ESMTP server not available

Server: 'smtp.talktalk.net'

Windows Live Mail Error ID: 0x800CCC6F

Protocol: SMTP

Port: 25

Secure(SSL): No

Regards,

Len.

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