Unable to send e-mails

[KeithG4]

I am no longer able to send e-mails from my pc using Windows 7 / Live Mail. Can still recieve e-mails, and a Windows 10 laptop appears to be able to send and recieve.

The error message is:

An unknown error has occurred.

Subject 'test tt'
Server Error: 421
Server Response: 421 Cannot connect to SMTP server 62.24.202.43 (62.24.202.43:25), connect error 10060
Server: 'smtp.talktalk.net'
Windows Live Mail Error ID: 0x800CCC67
Protocol: SMTP
Port: 25
Secure(SSL): No

Can this problem be quickly resolved as there was no problem prior to 8th July.

Regards
K.Gardner

[Gondola · Accepted solution]

Port 25 is blocked to stop insecure mail being sent.

Windows Live Mail does not support the secure mail required for TalkTalk Mail.

Good to know that your Windows 10 device is working. TalkTalk Mail webmail will also work although Windows 7 is now deprecated software that poses risks because of lack of security updates.

However, email software like Thunderbird is still supported for now on Windows 7 and will use secure mail by dint of the embedded TLS1.2 ciphers that are not supplied by Windows 7.