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An error occurred while sending mail. The mail server responded: you must enable authentication to use this mail server.

  • 2 replies
  • 2 have this problem
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  • Last reply by Peter Clark

Peter Clark
Peter Clark
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Hi,

My Thunderbird browser stopped sending emails yesterday. I rang my email provider and logged in to the webmail where I found I couldn't send from there either as my account had been black-listed. This was due to someone else accessing my account from abroad so I changed my email login and it seemed to have fixed the problem. I even sent a test email from Thunderbird to myself which worked OK.

This morning the problem has resurfaced on Thunderbird but my webmail is working fine. I got the following error message when i sent an email from Thunderbird: 

Sending of the message failed.

An error occurred while sending mail. The mail server responded: you must enable authentication to use this mail server.

This was the same error message that I got yesterday When the account had been black listed. I tried shutting down Thunderbird and restarting my computer but that didn't help. Any suggestions?

Regards Peter Clark pete1@slingshot.co.nz

Hi, My Thunderbird browser stopped sending emails yesterday. I rang my email provider and logged in to the webmail where I found I couldn't send from there either as my account had been black-listed. This was due to someone else accessing my account from abroad so I changed my email login and it seemed to have fixed the problem. I even sent a test email from Thunderbird to myself which worked OK. This morning the problem has resurfaced on Thunderbird but my webmail is working fine. I got the following error message when i sent an email from Thunderbird: Sending of the message failed. An error occurred while sending mail. The mail server responded: you must enable authentication to use this mail server. This was the same error message that I got yesterday When the account had been black listed. I tried shutting down Thunderbird and restarting my computer but that didn't help. Any suggestions? Regards Peter Clark pete1@slingshot.co.nz

Chosen solution

Try this for the outgoing server in Account Settings: smtp.slingshot.co.nz on port 587, STARTTLS security, authentication = normal password, User Name = part of email address before @.

For the incoming IMAP server: imap.slingshot.co.nz on 993, SSL/TLS, authentication = normal password, User Name = part of email address before @.

For the incoming POP server: pop3.slingshot.co.nz on 995, SSL/TLS, authentication = normal password, User Name = part of email address before @.

Change the settings, depending on the Server Type, remove entries from Saved Passwords in Settings/Privacy & Security, restart TB, enter the working account password when prompted.

https://help.slingshot.co.nz/hc/en-us/articles/360000087074-How-to-set-up-Slingshot-email-on-your-computer-or-device

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sfhowes
sfhowes
  • Top 10 Contributor
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Chosen Solution

Try this for the outgoing server in Account Settings: smtp.slingshot.co.nz on port 587, STARTTLS security, authentication = normal password, User Name = part of email address before @.

For the incoming IMAP server: imap.slingshot.co.nz on 993, SSL/TLS, authentication = normal password, User Name = part of email address before @.

For the incoming POP server: pop3.slingshot.co.nz on 995, SSL/TLS, authentication = normal password, User Name = part of email address before @.

Change the settings, depending on the Server Type, remove entries from Saved Passwords in Settings/Privacy & Security, restart TB, enter the working account password when prompted.

https://help.slingshot.co.nz/hc/en-us/articles/360000087074-How-to-set-up-Slingshot-email-on-your-computer-or-device

Peter Clark
Peter Clark Question owner
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Worked brilliantly. Thanks a heap!