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Cannot send outgoing mail after changing port to 465 or 587 for Comcast email.

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  • 1 has this problem
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  • Last reply by JoeB

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To better protect customers Xfinity user names and passwords, Effective today, Comcast is now blocking non-encrypted email settings. Customers must change outgoing mail server port to 465 or 587 and update outgoing mail server encryption settings to be able to send emails.

With Comcast tech support we went to Mail Account setup under the incoming field and selected IMAP. Server host name is imap.comcast.net. Then selected SSL/TLS. Port field was 993. Authentication method was Auto Detect

For outgoing, entered smtp.comcast.net. Selected STARTTLS. Port field was 587 and authentication method Autodetect.

We clicked on retest. Create account was not there and the word DONE became faint and could not be clicked on.

After doing all of this it was impossible to send an email.

To better protect customers Xfinity user names and passwords, Effective today, Comcast is now blocking non-encrypted email settings. Customers must change outgoing mail server port to 465 or 587 and update outgoing mail server encryption settings to be able to send emails. With Comcast tech support we went to Mail Account setup under the incoming field and selected IMAP. Server host name is imap.comcast.net. Then selected SSL/TLS. Port field was 993. Authentication method was Auto Detect For outgoing, entered smtp.comcast.net. Selected STARTTLS. Port field was 587 and authentication method Autodetect. We clicked on retest. Create account was not there and the word DONE became faint and could not be clicked on. After doing all of this it was impossible to send an email.

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I assume you got the problem fixed?

I probably wouldn't use Auto detect, if the value recommended for specific settings are available to choose in Tbird.

I recently changed one provider I use from default SMTP (so says Tbird) port 465 to the provider recommended 587 and for encryption, says, " STARTTLS, SSL/TLS or encryption.

Messages wouldn't go thru after changing it to port 587 w/ "SSL / TLS" selected.

Finally I tried STARTTLS w/ port 587 & it worked. But from what I've read (which could be outdated), using STARTTLS in Tbird - IF... the server doesn't support it can be bad.

A number of articles indicated if Tbird asks the server if it accepts STARTTLS and the answer's NO, then Tbird may (does?) send it unencrypted. Not sure on that.