This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Denc nañu waxtaan wii. Yónneel yeneen laaj soo soxlaa ndimbal.

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

  • 2 tontu
  • 1 am na jafe-jafe bii
  • 5 views
  • i mujjee tontu mooy christ1

lucky589
lucky589
more options

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)

lister171254
lister171254
more options

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

christ1
christ1
  • Top 25 Contributor
more options
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?