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Solved Cartlannaithe

Unable to send messages -- and it's not a firewall issue

Thunderbird Troubleshooting
duggabe replied 11 bliain ó shin
broccolisoup
broccolisoup

Hi everyone,

Yikes...I was able to send emails on Friday but now I’m unable to send -- just receive. Here’s the message I’m getting:

“Sending of message failed. The message could not be sent using SMTP server for an unknown reason. Please verify that your SMTP server settings are correct and try again, or contact your network administrator.”

I’ve checked all my settings, contacted the network admin and I don’t have firewalls (I'm on a MacBook Pro). I’m running 31.3.0 and I’ve changed no setting in over 3 months. More details:

POP Port 110 Outgoing Port: 2525 Default: 587 Authentication method: (I changed this to No Authentication from Normal after reading a few other threads) Connection security: STARTTLS

Any thoughts? I'm at a loss. Thank you for your help!

Hi everyone, Yikes...I was able to send emails on Friday but now I’m unable to send -- just receive. Here’s the message I’m getting: “Sending of message failed. The message could not be sent using SMTP server for an unknown reason. Please verify that your SMTP server settings are correct and try again, or contact your network administrator.” I’ve checked all my settings, contacted the network admin and I don’t have firewalls (I'm on a MacBook Pro). I’m running 31.3.0 and I’ve changed no setting in over 3 months. More details: POP Port 110 Outgoing Port: 2525 Default: 587 Authentication method: (I changed this to No Authentication from Normal after reading a few other threads) Connection security: STARTTLS Any thoughts? I'm at a loss. Thank you for your help!

All Replies (3)

duggabe
duggabe

Réiteach Roghnaithe

In your 'Outgoing Server (SMTP) Settings':

(a) try port 465; Authentication method: Normal password; Connection security: SSL/TLS

(b) try port 587; Authentication method: Password, transmitted insecurely; Connection security: None

If you have more than one Outgoing Server, check the 'Account Settings' page to see that the correct Outgoing Server is selected.

broccolisoup
broccolisoup Úinéir na ceiste

Duggabe -- thanks for your suggestion! Option (b) worked! But I have a question. What are the risks associated with transmitting email insecurely? Should this NOT be a long term solution?

Thank you again!

duggabe
duggabe

Yes, there is some concern. As a matter of fact, (a) is for my Google account, and (b) is for my website on a free host.

You or your network admin should ask the mail provider if there are any other options. In the practical sense though, it's only a risk on an insecure WiFi network where someone could snoop easily.

BTW, if you have a Google account, you can always use them to send, even if you receive from another provider! It works, as I have done that.