wrong "return emal" address

Question

suddenly , all my emails are being sent to clients with a Return email address , under the address i sent from, which is wrong. they are having to forward the emails to me. how do i fix this? i'm losing clients.

Answer 1

Hi Sandira Magnusson,

I understand that replies to your sent messages are going to an incorrect address, which is affecting communication with your clients.

Please note that this is a user-to-user forum, so contributors cannot access or modify your Outlook account.

Have you had a chance to try the suggestions in the Q&A Assist answer? I would also like to add one check that is more specific to the return address shown in classic Outlook:

1. Create a new email.
2. On the Options tab, select Direct Replies To.
3. Under Delivery options, check Have replies sent to.
4. If the incorrect address appears there, remove it or replace it with the correct address, then close the window and send a test message.

Because this is happening with every message, please confirm whether the account is Outlook.com or from another email provider, and whether the incorrect address is labelled Reply-To when the recipient opens the message. Please hide all email addresses in any screenshots.

I hope this helps determine whether Outlook or the email account is adding the return address.

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Answer 2

If Outlook for Windows is adding the wrong return address under the address being used to send, the most likely causes in the available guidance are:

1. A false reply/return address is configured and the mail server is rejecting or rewriting it. Some providers block a reply address that does not match the current connection domain. In that case, the return email address must match the current connection domain.
2. The account was added in a way that causes Outlook to send from an incorrect Outlook.com alias-style address such as outlook_[long string]@outlook.com.
3. A forwarding or rule setting is redirecting mail unexpectedly.

Try these steps in order:

1. Check Outlook.com forwarding and rules
   • In Outlook on the web, go to Settings > View all Outlook settings > Mail > Rules.
   • Remove any rule that forwards, redirects, or auto-replies using an address that is not correct.
   • Then go to Mail > Forwarding and make sure forwarding is off, or remove any wrong address.
2. Check aliases if the account uses Outlook.com / Microsoft account aliases
   • If there are multiple aliases and a third-party address is the primary alias, Outlook can send with the wrong address format.
   • Remove any unrecognized alias and make sure the correct address is the one intended for sending.
3. If Outlook for Windows shows or sends from an outlook_[long series]@outlook.com address, recreate the profile and set the account up manually
   • Close Outlook.
   • Press Windows key + R, type outlook /profiles, then select OK.
   • In Choose Profile, select Options > New.
   • Enter a unique profile name.
   • Choose Advanced options > Let me set up my account manually.
   • Enter the password and select Connect.
   • If setup fails, select Change Account Settings and enter the POP/IMAP settings from the mail provider or from the POP and IMAP server name reference.
   • Finish setup, then in Choose Profile select Set as default profile.
4. If replies/forwards in Outlook 2019 show a blank sender address like < >, update Outlook
   • This was fixed in Outlook 2019 build 10388.20004.
   • In Outlook, go to File > Account > Update Options > Enable Updates.
5. If sending still fails after changing the return address
   • The mail provider or ISP may be blocking identity spoofing.
   • In that case, the return/reply address must use the same domain as the current connection.

If this started suddenly and no profile issue is visible, checking Rules, Forwarding, and aliases first is the fastest path because those can cause mail to appear redirected or to use the wrong return path.

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References:

• Email sent from wrong address
• Outlook.com email account appears as "outlook_[long series of letters and numbers]@outlook.com" in Outlook for Windows
• Outlook 2019 sender email address missing on reply and forwards
• I receive a 550, 553, or relay-prohibited error when sending email messages
• When someone sends me an email, they receive Delivery has failed to these recipients or groups with a different email address to mine? - Microsoft Q&A
• Outlook is informing my recipients that my message was redirected to a different address. - Microsoft Q&A
• email forwarding by asp-relay-shared.jellyfish.systems - Microsoft Q&A