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How to fix Email delivery failed - 552 5.2.0 invalid 7bit data.

  • 2 replies
  • 1 has this problem
  • 5 views
  • Last reply by christ1

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I am getting the following error message when sending emails to certain people I routinely send to. The bounce back error is: 552 5.2.0 Invalid 7bit data. How can I fix this? What does the error message mean? Is this a problem on my end or recipient?

I am getting the following error message when sending emails to certain people I routinely send to. The bounce back error is: 552 5.2.0 Invalid 7bit data. How can I fix this? What does the error message mean? Is this a problem on my end or recipient?

All Replies (2)

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I think this is the same issue as https://support.mozilla.org/en-US/questions/1235645

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1and1 tried to see if there was anything on their end to fix but nothing worked.

Is 1and1 your email provider or the recipients email provider?

If not, is the recipients email provider Orange/Wanadoo or another one?

If another one, who is it?