Cant send emails via Outlook 365 since going to 5G home broadband

[njbucket]

Hi,

We recently upgraded from NBN to TPG 5G home broadband.  Since doing so, we cant send emails from Outlook 365.  The messages sit in the outbox, and give the following send/receive error message:

Reported error (0x80042109) : 'Outlook cannot connect to your outgoing (SMTP) email server.  If you continue to receive this message, contact your server administrator or internet service provider (ISP).'

We have confirmed the servers and ports are per TPG email setup instructions.

Interestingly, if we tether an i-phone, the messages send OK.

Any help appreciated.

Thanks

[david64]

Hi @njbucket . If you are using TPG's instructions, you are probably using port 25 for sending. Can you try port 587.

[njbucket]

Hi @david64 

Thanks heaps! We are back in business!

It would be good if TPG updated their reference documents regarding mail setup to include this info.

At the risk of asking a dumb question, could you please explain why the outgoing port changed with the change of our home broadband from NBN to 5G broadband?

Why did tethering an iPhone allow outgoing mail with the old port 25 setting?

Thanks

[david64 · Accepted solution]

@njbucket . Don't know why port 25 is blocked on 5G (and maybe 4G also). Might be something in the mobile network or TPG's connection to it. 

For sending (port 587) and receiving (port 110), you can add encryption. Select STARTTLS in security setting.

Regarding the iphone, is it with TPG or another service? If TPG, then there is some distinction between mobile phone traffic and wireless broadband. Otherwise, it is up to the provider.