Email issue

[#1]

Are you sending to multiple recipients in the same email? If not, and the fact that it sends OK back on your home connection is strange, to say the least. This needs an expert to solve, as it is outside my knowledge.

@MisterW  / @Townman - any thoughts?

Gmail is totally divorced from Plusnet, so is not relevant here.

[#2]

It happens whether I send to a single recipient or multiple recipients

[#3]

Message says 'Cannot send email - The server rejected one of the of the repents addresses. Message in the Outbox"

That message is just a standard one from the mail client not being able to send. It's nothing to do with the recipients address , its just failing to send at all.

@JBL my guess is that the IP address you're assigned on the mobile network is blacklisted. Leave it 24 hrs and see if it clears.

The problem with mobile networks is that IP addresses are shared between many users via CGNAT and thus anyone being 'naughty' and sending spam can cause the Plusnet mail server to blacklist.

[#4]

I think I want to pick apart the details here; you are using...

• Apple Mail
• On an iMac
• Connection to a MOBILE network ... how?

If this were being experienced on an iPhone I would recommend putting it in to AEROPLANE mode for an hour and then try again after reconnecting to the mobile network.

Third party network connections can be abused and if detected the IP addresses will be black-balled.  Mobile networks tend to use NAT so there could be hundreds of devices using the same public IP address.

Have you been able to send email over mobile in a different location?

[#5]

Thanks for your help. Perhaps I am a bit out of mu depth! To be clear -

1. When using my iPhone, I can only send email using my plus.com email address when on wi-fi

2. This is the case when at home with W-Fi disconnected or away from home - if on mobile data email is not delivered until Wi-Fi is back on

3. Instead I am able to send emails via mobile data using an alternative email address (eg gmail)

4. This has always been the case, it;s not just a recent problem. - I have lived with it and could continue to do so - it;s just annoying!

Hope this makes sense

My theory his that it's something to do with email settings on Apple Mail - but that's only a theory!!!

[#6]

When using my iPhone, I can only send email using my plus.com email address when on wi-fi

@JBL so its nothing to do with an iMac ? its only a problem with an iPhone.

I think at this point we'll let @Townman  take over, he's much more familar with Apple stuff...

[#7]

Correct! The only reason I mentioned the iMac was because someone posted out that it could be to do with settings on the desktop!

[#8]

When you've been checking the settings for the outgoing server, have you been checking on the iMac or iPhone ?

To confirm, its the settings on the iPhone that need to be checked for using authenication.

[#9]

Thanks. But (dummy's question) what re the right settings?

[#10]

Basically as previously advised, your need to configure authenication on the outgoing(smtp) server using your plusnet credentials

For completeness

Host Name - relay.plus.net
User Name  - your plusnet account name
Password - your account password
Authentication - Password
Server Port - 587

and if there's an SSL/TLS box then check it

[#11]

This is what the smtp settings should be on an iPhone…

Username should be accountname+mailboxname