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I can't send emails any more, since yesterday. I get an error message saying, in part "... Requested action not taken: mailbox unavailable Failure sending mail

  • 3 replies
  • 1 has this problem
  • 10 views
  • Last reply by sfhowes

IanStar
IanStar
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I can't send emails any more, since yesterday. I get an error message saying, "An error occurred while sending mail. The mail server responded: Requested action not taken: mailbox unavailable. Failure sending mail. Try again later. Please check the message recipient "xxxxxxxxxxx@mail.com" and try again"

Interestingly, if I select another email address (gmail in this case) as the sender, it sends OK.

Edit: This has proved to be an intermittent problem! Sometimes I can send test emails to myself, sometimes I can't.

Mail provider: mail.com ISP: ??? USB or wireless tether to mobile phone. Anti-virus: Windows Firewall Windows version: Windows 7 Professional ©2009 Thunderbird 52.9.1 (32-bit)

I can't send emails any more, since yesterday. I get an error message saying, "An error occurred while sending mail. The mail server responded: Requested action not taken: mailbox unavailable. Failure sending mail. Try again later. Please check the message recipient "xxxxxxxxxxx@mail.com" and try again" Interestingly, if I select another email address (gmail in this case) as the sender, it sends OK. Edit: This has proved to be an intermittent problem! Sometimes I can send test emails to myself, sometimes I can't. Mail provider: mail.com ISP: ??? USB or wireless tether to mobile phone. Anti-virus: Windows Firewall Windows version: Windows 7 Professional ©2009 Thunderbird 52.9.1 (32-bit)
Attached screenshots

Modified by IanStar

All Replies (3)

amandasey
amandasey
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Get Help here: https://support.mozilla.org/en-US/kb/cannot-send-messages

IanStar
IanStar Question owner
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Tried the troubleshooter options above, to no avail. Mail.com suggests it's the SMTP setting in Thunderbird which is causing the (intermittent) problem, and that I should upgrade to Premium.

sfhowes
sfhowes
  • Top 25 Contributor
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According to their website, the smtp settings (for Premium accounts) are smtp.mail.com on port 587, Connection security = none, authentication = password, transmitted insecurely, User name = email address. But another page recommends: smtp.mail.com on port 465, SSL/TLS security, normal password authentication. And yet a third source suggests smtp.mail.com on port 587, STARTTLS security, normal password authentication.

There's no indication their non-Premium service supports mail access with 3rd-party programs like TB. That would explain a 'mailbox unavailable' error.