MS Outlook not sending emails

[SpikeyJohn]

I've used Outlook for years to send and receive my emails but for the last week or so I've had problems sending (receiving emails is not a problem).  I get the following error message ;

Task obscured for customer security - Sending' reported error (0x800CCC67) : ' The server responded: 421 Cannot connect to SMTP server 62.24.202.43 (62.24.202.43:25), connect error 10060'

Is this an issue with Talktalk email or have I somehow broken Outlook ?

[Gondola]

It's actually an action of last resort by TalkTalk to stop the use of insecure mail. Users have just dismissed many past notifications to use secure mail software and secure settings.

But let me know what your device operating system is and if Windows 10 or 11 then the upgrade path is either Windows Mail included with the Windows package or a paid upgrade to Outlook 16 - 365 or a free upgrade to an email client like Thunderbird or BlueMail desktop email app. I'll help you get back in action if needed.

You've always got TalkTalk Mail's webmail app to keep in touch with contacts.

Select here:  Sign in to TalkTalk Mail

Enter your full TalkTalk Mail email address and password, select Sign in.

[SpikeyJohn]

Sorry, when you said personal domain I wasn't sure what you meant.  I'm using my talktalk email address if that's what you mean ?  If I can't use outlook to send my emails I guess I'll have to find an alternative.  Bit peeved that this has just happened all of a sudden though.  Thanks for your help !!

[Gondola]

Let me know what your preferred upgrade is for Outlook 2010 and I'll help with the setup if you need assistance.

[Gondola]

Yes, port 25 is blocked to stop unauthorised and insecure mail sending.  You may not use the TalkTalk Mail servers for personal domain sending. You should use the outgoing SMTP servers provided by the mail hosting service you're using.

Outlook 2010 is also inherently insecure and does not support, for TalkTalk Mail, the StartTLS command for outgoing authenticated mail and therefore is recommended for retirement from use.

MacMail will be good so long as the MacOS is 10.12 Sierra or later in order to support the secure mail encryption by TLS 1.2 protocol as required by TalkTalk Mail.

[SpikeyJohn]

Thanks for getting back to me.  I appear to be using Outlook 2010 but it's only in the last week that I've had any issues.  I've not changed anything in Outlook at all, it's just suddenly started to have a problem with sending emails after years of working seamlessly.  "are you sending mail from your personal domain address using the TalkTalk servers?"  - I guess so, has something changed ?

[Gondola]

I've removed your email address to protect you from spammers.

What version of Outlook are you using?  TalkTalk Mail supports Outlook 2016 or newer.

The 421 error means that the server is not available because you're using port 25 and that port is blocked.

Also, are you sending mail from your personal domain address using the TalkTalk servers? That's no longer going to work.

Each email account requires User name (full email address) and password authentication for both incoming and outgoing mail using the same User name and password for both incoming and outgoing mail servers.