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Sending of the message failed.

  • 4 replies
  • 1 has this problem
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  • Last reply by sfhowes

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Why this message when trying to send e-mails? Receiving is no problem. "Sending of the message failed. Failed due to unexpected error 80004005. No description is available. The message could not be sent using Outgoing server (SMTP) z9.smtp.startmail.com for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again."

Why this message when trying to send e-mails? Receiving is no problem. "Sending of the message failed. Failed due to unexpected error 80004005. No description is available. The message could not be sent using Outgoing server (SMTP) z9.smtp.startmail.com for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again."

Chosen solution

As they state on the provided link, the account password is for logging in on startmail.com, but for mail clients you must use a 'generated password'. Remove the passwords in Saved Passwords in Options/Privacy & Security, restart TB, enter a generated password when prompted.

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Are you sending on smtp.startmail.com, port 587, STARTTLS, normal password? Is the password the account password or the 'generated password'?

https://support.startmail.com/hc/en-us/articles/360006596718-Server-addresses

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Are you sending on smtp.startmail.com, port 587, STARTTLS, normal password? Is the password the account password or the 'generated password'?

https://support.startmail.com/hc/en-us/articles/360006596718-Server-addresses

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The outgoing server is z9. smtp.startmail.com, port 587, STARTTLS, normal password. Don´t know why the"z9." Deleting it doesn´t help. The password is the account password. I can log in on startmail.com with that password and send messages from there.

I have used Thunderbird for years without any problems and with the same settings all the time. My impression is that todays problem started after an update - can´t tell when or which one.

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Chosen Solution

As they state on the provided link, the account password is for logging in on startmail.com, but for mail clients you must use a 'generated password'. Remove the passwords in Saved Passwords in Options/Privacy & Security, restart TB, enter a generated password when prompted.