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Cannot send emails - error code 5.5.1- cannot fix

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  • Paskiausią atsakymą parašė Matt

ckwalker
ckwalker
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One day my ability to send emails just stopped. The message said, "An error occurred while sending mail. The mail server responded: 5.5.1 Invalid command. Please verify that your address is correct in your account setting and try again." I have checked everything I can and have not discovered any incorrect information regarding the email address. I am able to receive emails as always. What should I do to be able to send emails again. (Can send emails on two Kindles and my desktop computer).

One day my ability to send emails just stopped. The message said, "An error occurred while sending mail. The mail server responded: 5.5.1 Invalid command. Please verify that your address is correct in your account setting and try again." I have checked everything I can and have not discovered any incorrect information regarding the email address. I am able to receive emails as always. What should I do to be able to send emails again. (Can send emails on two Kindles and my desktop computer).

All Replies (1)

Matt
Matt
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  • Top 10 Contributor
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In order for us to better investigate this issue you need to add a little more non-personal information.

Please add the troubleshooting information to your post To find the Troubleshooting information:

  • Open Help (or click on three-line-icon and select Help)
  • Choose Troubleshooting Information
  • Use the button Copy to clipboard to select all. Do not check box "Include account names"!
  • Paste this in your post.

Please also add the result of these troubleshooting steps to your post

  • Does Thunderbird work in TB Safe mode (see Thunderbird Safe Mode)?
  • Do you use anti-virus and firewall software? What is the version?