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sending to "gmail" addresses

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I can not send emails to gmail & optusnet addresses they bounce back. See example below.

[email protected]
   host extmail.optusnet.com.au [211.29.133.14]
   SMTP error from remote mail server after RCPT TO:<[email protected]>:
   550 5.1.1 <[email protected]>: Recipient address rejected:
   User unknown in virtual mailbox table
 [email protected]
   host gmail-smtp-in.l.google.com [74.125.200.27]
   SMTP error from remote mail server after end of data:
   550-5.7.26 This mail is unauthenticated, which poses a security risk to the
   550-5.7.26 sender and Gmail users, and has been blocked. The sender must
   550-5.7.26 authenticate with at least one of SPF or DKIM. For this message,
   550-5.7.26 DKIM checks did not pass and SPF check for [pnc.com.au] did not pass
   550-5.7.26 with ip: [203.42.40.162]. The sender should visit
   550-5.7.26  https://support.google.com/mail/answer/81126#authentication for
   550 5.7.26 instructions on setting up authentication.

s33-20020a635261000000b005533a94a2fdsi17542751pgl.466 - gsmtp

I can not send emails to gmail & optusnet addresses they bounce back. See example below. [email protected] host extmail.optusnet.com.au [211.29.133.14] SMTP error from remote mail server after RCPT TO:<[email protected]>: 550 5.1.1 <[email protected]>: Recipient address rejected: User unknown in virtual mailbox table [email protected] host gmail-smtp-in.l.google.com [74.125.200.27] SMTP error from remote mail server after end of data: 550-5.7.26 This mail is unauthenticated, which poses a security risk to the 550-5.7.26 sender and Gmail users, and has been blocked. The sender must 550-5.7.26 authenticate with at least one of SPF or DKIM. For this message, 550-5.7.26 DKIM checks did not pass and SPF check for [pnc.com.au] did not pass 550-5.7.26 with ip: [203.42.40.162]. The sender should visit 550-5.7.26 https://support.google.com/mail/answer/81126#authentication for 550 5.7.26 instructions on setting up authentication. s33-20020a635261000000b005533a94a2fdsi17542751pgl.466 - gsmtp

All Replies (3)

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Firefox isn't a email program so not sure what site your using to email but this is a email issue not a Firefox issue.

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Hi there,

Based on the error messages you provided, it seems that you are experiencing issues sending emails to Gmail and Optusnet addresses. The error messages indicate that the recipient addresses are being rejected by the respective mail servers.

For the Optusnet address ([email protected]), the error message suggests that the recipient address is unknown in the virtual mailbox table of the Optusnet mail server. This could be due to an incorrect or inactive email account.

For the Gmail address ([email protected]), the error message states that the email is unauthenticated, posing a security risk. The sender needs to authenticate with at least one of SPF or DKIM to ensure the email's authenticity. The error also mentions that the DKIM checks did not pass and the SPF check for [pnc.com.au] did not pass with the given IP address. It is recommended to follow the instructions provided in the error message and visit the Google support page on email authentication for further guidance.

As a Firefox Support Forum contributor, you can provide the following information to assist the user:

Advise the user to double-check the recipient email addresses for any typos or errors. Suggest contacting the respective email service providers (Optusnet and Gmail) for further assistance regarding the specific error messages. Recommend reviewing the email authentication settings, such as SPF and DKIM, and ensuring they are properly configured for the sending domain (pnc.com.au in this case). Please note that these suggestions are based on the information provided, and further troubleshooting or assistance from the email service providers may be required to resolve the issue.

Hope this helps! Let me know if you have any other questions or need further assistance.

Best regards, Firefox Support Forum Volunteer

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Is this problem unique to using your mail provider's site in Firefox? In other words, can you send to those addresses if you sign into your mail provider's site in Internet Explorer, Google Chrome, or another third party browser?

If you are having this problem in Thunderbird (the stand-alone email program), a moderator can move your question to the Thunderbird forum.