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why do I get an error on sent messages after changing ISP using thunderbird

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  • 1 has this problem
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  • Last reply by Matt

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I changed ISP from Plusnet to 4Ginternet. I still have a Plusnet email account. Now when I try and send emails using Thunderbird I get this error message:
'An error occurred while sending mail. The mail server responded:
<[REDACTED BY MODERATOR]@btinternet.com> recipient rejected - relay denied.
Please check the message recipient "[REDACTED BY MODERATOR]@btinternet.com" and try again.'
It does not matter who the recipient is; same message.
If I reconnect to the Plusnet router then emails are sent successfully. So nothing in settings has been changed. Similarly using Plusnet webmail page sending emails works.
Who is at fault, 4G, Thunderbird or Plusnet, me?
Very confusing and annoying

[Personal information removed by moderator. Please read Mozilla Support rules and guidelines, thanks.]

I changed ISP from Plusnet to 4Ginternet. I still have a Plusnet email account. Now when I try and send emails using Thunderbird I get this error message:<br/> 'An error occurred while sending mail. The mail server responded: <br/> <''[REDACTED BY MODERATOR]''@btinternet.com> recipient rejected - relay denied.<br/> Please check the message recipient "''[REDACTED BY MODERATOR]''@btinternet.com" and try again.'<br/> It does not matter who the recipient is; same message. <br/> If I reconnect to the Plusnet router then emails are sent successfully. So nothing in settings has been changed. Similarly using Plusnet webmail page sending emails works.<br/> Who is at fault, 4G, Thunderbird or Plusnet, me?<br/> Very confusing and annoying ''[Personal information removed by moderator. Please read [[Forum rules and guidelines]], thanks.]''

Modified by Chris Ilias

All Replies (1)

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how did you change your settings in Thunderbird to accommodate the change to 4Ginternet?

There are a number of possibilities, but basically it sounds like either you have updated Thunderbird to send mail using your 4g SMTP server and your plusnet address, so the 4g is refusing to accept outgoing mail for some other mail server, or You have set Thunderbird to send mail to your old SMTP where you no longer have an account to send mail so the recipient is not accepted as you are not able to authenticate.

Perhaps is you were to go to the troubleshooting information on the help menu of Thunderbird and copy that to the clipboard and paste it into a reply on the forum I might be able to guess which it is.