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Sending of the message failed.

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Been using Thunderbird for years. Today while trying to send an e-mail I get this: "Sending of the message failed. An error occurred while sending mail. The mail server responded: See http://pobox.com/~djb/docs/smtplf.html.. Please check the message and try again."

I read the link and I have no idea what that means.

Using Win 10 and Thunderbird 102.1.0 (64-bit)

Been using Thunderbird for years. Today while trying to send an e-mail I get this: "Sending of the message failed. An error occurred while sending mail. The mail server responded: See http://pobox.com/~djb/docs/smtplf.html.. Please check the message and try again." I read the link and I have no idea what that means. Using Win 10 and Thunderbird 102.1.0 (64-bit)

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I also contacted my host and this was their response:

Recently, we received several reports for outgoing mail issues following a recent AVG or Avast antivirus update. If you are using either of these applications, or any other antivirus/firewall app on your computer, please disable them for a quick test.

Since disabling your antivirus program permanently is not recommended, you may try disabling the signature in the application. Instructions are available at:

https://support.avast.com/en-us/article/antivirus-email-signature/#pc

https://support.avg.com/SupportArticleView?l=en&urlName=AVG-Antivirus-email-signature&supportType=home

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I contacted my host too and this was their response:

Recently, we received several reports for outgoing mail issues following a recent AVG or Avast antivirus update. If you are using either of these applications, or any other antivirus/firewall app on your computer, please disable them for a quick test.

Since disabling your antivirus program permanently is not recommended, you may try disabling the signature in the application. Instructions are available at:

https://support.avast.com/en-us/article/antivirus-email-signature/#pc

https://support.avg.com/SupportArticleView?l=en&urlName=AVG-Antivirus-email-signature&supportType=home

Modified by Mike Matenkosky

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Chosen Solution

I also contacted my host and this was their response:

Recently, we received several reports for outgoing mail issues following a recent AVG or Avast antivirus update. If you are using either of these applications, or any other antivirus/firewall app on your computer, please disable them for a quick test.

Since disabling your antivirus program permanently is not recommended, you may try disabling the signature in the application. Instructions are available at:

https://support.avast.com/en-us/article/antivirus-email-signature/#pc

https://support.avg.com/SupportArticleView?l=en&urlName=AVG-Antivirus-email-signature&supportType=home