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Unable to Send Emails

  • 3 replies
  • 0 have this problem
  • 16 views
  • Last reply by JP

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Starting today, I cannot send an email either via Thunderbird on my Mac (MacOS Montery 12.4) or using the mail app on my iPhone. I can receive emails. If I use the Outlook app on my Mac or the browser, I can send and receive emails. My outgoing settings are: Outlook.com smtp.office365.com 587 xxxxxxxxx@outlook.com Normal PW STARTTLS

My ISP is COX and there are no virus programs

Thanks so much.

Kim Saal

Starting today, I cannot send an email either via Thunderbird on my Mac (MacOS Montery 12.4) or using the mail app on my iPhone. I can receive emails. If I use the Outlook app on my Mac or the browser, I can send and receive emails. My outgoing settings are: Outlook.com smtp.office365.com 587 xxxxxxxxx@outlook.com Normal PW STARTTLS My ISP is COX and there are no virus programs Thanks so much. Kim Saal

All Replies (4)

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Hello there Kim. We have read your message. We try to help you.


It seems that your app or settings for your Mac are not working as it should. For further instructions to solve this problem on your Mac book. I can send you a form with more details to follow?

Do you like to recieve this form online? So I can send you that right away.


Greetings Firefox volunteer.

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yes please

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Hello there again.


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

Send me a message if. Thing does not solve.

https://support.mozilla.org/en-US/kb/uninstall-thunderbird Try to uninstall both icones on your device s also from your mobile device. Do not reinstall the one on the mobile device.


Start up in safe modus for pc or MacBook for Thunderbird . Check if you can send messages now while in safe modus. https://support.mozilla.org/en-US/kb/troubleshoot-mode-thunderbird


Greetings firefoxvolunteer.

Modified by Googlethunderbird

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ksaal wrote

Starting today, I cannot send an email either via Thunderbird on my Mac (MacOS Montery 12.4) or using the mail app on my iPhone. I can receive emails. If I use the Outlook app on my Mac or the browser, I can send and receive emails. My outgoing settings are: Outlook.com smtp.office365.com 587 xxxxxxxxx@outlook.com Normal PW STARTTLS

as per https://support.microsoft.com/en-us/office/pop-imap-and-smtp-settings-for-outlook-com-d088b986-291d-42b8-9564-9c414e2aa040 the SMTP server is smtp-mail.outlook.com