Apologies for the length of this message but I have seen several people with similar issues to the one I am experiencing and several solutions suggested - none of which seem to resolve my problem. So I'm giving what I hope are full and clear details in the hope that one of you good people can help me.
Background
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For several years I have used a web-hosting company to provide an internet domain with some email addresses. Let's call these email addresses 123@webhosting.co.uk and 987@webhosting.co.uk (in fact there are four of them, but you get the picture).
I've also got a number of Gmail addresses. Let's call these abc@gmail.com and xyz@gmail.com (again, for illustative purposes only).
I handle all these addresses using Thunderbird.
I've had BT as my ISP for just over a month. Prior to that, this setup has worked without any significant problems.
The issue
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As of yesterday all attempts to send outbound email from the four @webhosting.co.uk addresses have resulted in the following error message:
An error occurred while sending mail. The mail server responded:
5.7.1 <recipient email address>: Recipient address rejected: Access denied.
Please check the message recipient "recipient email address" and try again.
There is no problem with outbound emails sent from my Gmail accounts and no problem with inbound emails coming in to any of my email addresses.
The investigation
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I've come to the conclusion that the problem must be due to the SMTP Outbound Server settings for my @webhosting.co.uk email accounts. They all use the same setiings, namely:
Server Name: smtp.webhosting.co.uk
Port: 465
User name: 123@webhosting.co.uk OR 987@webhosting.co.uk, etc
Authentication: Normal password
Security: SSL/TLS
From what I've read on this forum these seem to be reasonable settings. But in an attempt to find a solution I have tried port numbers 587 and 25 - with no change.
I've also tried different combinations of Authentication and Security settings but these tend to result in a "timeout" error when sending.
Why do I think the problem lies with BT and not with webhosting.co.uk ? Simply because if I disconnect from the BT hub and connect to an O2 dongle - thereby taking BT out of the equation altogether - the problem disappears. My current settings work perfectly OK. Emails to all accounts are sent and received with no problems.
Can anyone offer any advice ? Anything I haven't tried yet that I should have ? I don't want to have to keep a dongle topped up simply because BT can't handle emails coming from my @webhosting.co.uk email addresses.
