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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

Thunderbird Troubleshooting
IanStar replied
IanStar
IanStar

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 (2)

amandasey
amandasey

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

IanStar
IanStar Question owner

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.