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Thunderbird receives email but won't send email

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  • 3 have this problem
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  • Last reply by lifeorigin

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A few weeks ago Thunderbird stopped allowing me to send emails. New emails I receive download fine. Here is the error message I'm getting:

An error occurred while sending mail. The mail server responded: 550 5.1.0 Authentication required. Please verify that your email address is correct in your account settings and try again.

I've checked that my email address is correct and that my outgoing server is smtp.comcast.net but that is the extent of my knowledge of what I can check. I hadn't changed any settings and this just started happening.

Help would be very appreciated! Thanks in advance! Linda

A few weeks ago Thunderbird stopped allowing me to send emails. New emails I receive download fine. Here is the error message I'm getting: ''An error occurred while sending mail. The mail server responded: 550 5.1.0 Authentication required. Please verify that your email address is correct in your account settings and try again.'' I've checked that my email address is correct and that my outgoing server is smtp.comcast.net but that is the extent of my knowledge of what I can check. I hadn't changed any settings and this just started happening. Help would be very appreciated! Thanks in advance! Linda

Chosen solution

You can check that the SMTP authentication is set to normal password, the error message indicates it is set to none and that is not acceptable to comcast.

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Seçilmiş Həll

You can check that the SMTP authentication is set to normal password, the error message indicates it is set to none and that is not acceptable to comcast.

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Thanks you so much, Matt. Problem solved!

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My verizon.net email goes through AOL.com I have all the right settings confirmed by AOL.com technicans. Thunderbird sometimes sends emails, and sometimes won't, almost daily.

They say Thunderbird is the problem.