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Thunderbird screwed up - Can't send or receive email after "Lightning" .

  • 1 phendula
  • 1 inayo le ngxaki
  • 2 views
  • Impendulo yokugqibela ngu Matt

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Following pop-up when trying to send (no errors in my settings)

"Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) smtp.comcast.net failed. The server may be unavailable or is refusing Outgoing server (SMTP) connections. Please verify that your Outgoing server (SMTP) settings are correct and try again".

Also unable to receive incoming. CAN send and receive with Comcast. Comcast assures me that problem is known but not at their end.

Following pop-up when trying to send (no errors in my settings) "Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) smtp.comcast.net failed. The server may be unavailable or is refusing Outgoing server (SMTP) connections. Please verify that your Outgoing server (SMTP) settings are correct and try again". Also unable to receive incoming. CAN send and receive with Comcast. Comcast assures me that problem is known but not at their end.

All Replies (1)

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Well if Comcast know what the problem is they might deign to share that knowledge. Instead I am going to start you on a lengthy diagnostic process to try and work it out.

Common problems with Comcast include.

  • Old modems
  • Changed email settings for Comcast.
  • Anti virus software.


To diagnose problems with Thunderbird, try the following:

  • Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
  • Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 8, Windows 7, Windows Vista, Windows XP, OSX
If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.