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Cannot send emails.

  • 4 replies
  • 2 have this problem
  • 4 views
  • Last reply by alanyuen

alanyuen
alanyuen
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This is the error message that I get is An error occurred while sending mail. The mail server responded: Request failed; Mailbox unavailable. Please check the message and try again. I am using Sky Yahoo Mail, Windows 10 Firewall and Anti virus, Windows 10 version 1809, Thunderbird 45.7.1 There has been no recent update to Windows 10 and Thunderbird. Have been unable to send emails in the last 3 days. Tried to attach screen shot of the Outgoing server SMTP settings, but system fail to attach png file of screen shot, but here are details of selected server: smtp.tools.sky.com 465 Normal password SSL/TLS

Grateful for your assistance.

This is the error message that I get is ''An error occurred while sending mail. The mail server responded: Request failed; Mailbox unavailable. Please check the message and try again.'' I am using Sky Yahoo Mail, Windows 10 Firewall and Anti virus, Windows 10 version 1809, Thunderbird 45.7.1 There has been no recent update to Windows 10 and Thunderbird. Have been unable to send emails in the last 3 days. Tried to attach screen shot of the Outgoing server SMTP settings, but system fail to attach png file of screen shot, but here are details of selected server: smtp.tools.sky.com 465 Normal password SSL/TLS Grateful for your assistance.

Chosen solution

I don't have a Yahoo account to test, but the link in my first reply suggests you have to remove and then add the account as a send-only address in Yahoo settings and follow the steps to verify it.

https://help.yahoo.com/kb/SLN28342.html

Read this answer in context 👍 1

All Replies (4)

sfhowes
sfhowes
  • Top 10 Contributor
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Do you have a 'non-registered' reply-to address in your outgoing mail?

https://support.mozilla.org/en-US/questions/1260312

Note that AT&T, Verizon, AOL, Rogers etc. all use Yahoo mail systems.

alanyuen
alanyuen Question owner
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Many thanks. I removed reply-to address from Thunderbird and I can send mail. But how do I register reply-to address. Using Yahoo Mail from the web, I have the same reply-to address there and it works if I send mail from Web.

sfhowes
sfhowes
  • Top 10 Contributor
more options

Chosen Solution

I don't have a Yahoo account to test, but the link in my first reply suggests you have to remove and then add the account as a send-only address in Yahoo settings and follow the steps to verify it.

https://help.yahoo.com/kb/SLN28342.html

alanyuen
alanyuen Question owner
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Many many thanks. It's working as before. Just don't know why it suddenly did not work.