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outgoing e-mail

david7.bates
david7.bates
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I am using v. 91.9.1 of Thunderbird e-mail

I have been running 4 e-mail addresses, all with BT.

This last week 2 of those addresses have stopped sending outward messages although I haven't changed anything in Thunderbird or BT.

The other 2 addresses work for both in & outgoing mail.

On the failed outgoing mail I get the following message:- "Sending of the message failed. Unable to authenticate to Outgoing server (SMTP) mail.btinternet.com. Please check the password and verify the 'Authentication method' in 'Account Settings | Outgoing server (SMTP)'." BT says they can't help. The problem is with Thunderbird??

Any ideas ? Regards David Bates

I am using v. 91.9.1 of Thunderbird e-mail I have been running 4 e-mail addresses, all with BT. This last week 2 of those addresses have stopped sending outward messages although I haven't changed anything in Thunderbird or BT. The other 2 addresses work for both in & outgoing mail. On the failed outgoing mail I get the following message:- "Sending of the message failed. Unable to authenticate to Outgoing server (SMTP) mail.btinternet.com. Please check the password and verify the 'Authentication method' in 'Account Settings | Outgoing server (SMTP)'." BT says they can't help. The problem is with Thunderbird?? Any ideas ? Regards David Bates

Chosen solution

Hello there again.


Since it has the issue to not send messages. Something’s wrong at the settings. Check all Smtp settings for your mail activities.

Check and change if that is possible the password s for pop and Imap

Go to Tools > Preferences > Privacy and Security > Click on Saved passwords then click on Show passwords. Right click on the password you want to change and click on Edit password.

Check in meanwhile the Smtp settings for your Software. Are you using security software for protection? Also with add on?


https://support.mozilla.org/en-US/kb/cannot-send-messages

https://support.mozilla.org/en-US/kb/manual-account-configuration

Greetings Firefox volunteer.

Read this answer in context 👍 0

All Replies (2)

Googlethunderbird
Googlethunderbird
  • Top 25 Contributor
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Hello there David7. Bates.

We have read your message. We try to help you.

The outgoing settings for the outgoing Smtp server gives you a message that something not oké with your settings in the Smtp setting for Thunderbird.

check your username and security password for spelling errors


Greetings Firefox volunteer.

Modified by Googlethunderbird

Googlethunderbird
Googlethunderbird
  • Top 25 Contributor
more options

Chosen Solution

Hello there again.


Since it has the issue to not send messages. Something’s wrong at the settings. Check all Smtp settings for your mail activities.

Check and change if that is possible the password s for pop and Imap

Go to Tools > Preferences > Privacy and Security > Click on Saved passwords then click on Show passwords. Right click on the password you want to change and click on Edit password.

Check in meanwhile the Smtp settings for your Software. Are you using security software for protection? Also with add on?


https://support.mozilla.org/en-US/kb/cannot-send-messages

https://support.mozilla.org/en-US/kb/manual-account-configuration

Greetings Firefox volunteer.

Modified by Googlethunderbird