Forum Discussion
Reply-To' Header Being Stripped in Office 365 Emails
Hi everyone, we are experiencing an issue where the "Reply-To" header in emails sent to our Exchanged hosted email account is being stripped. This behaviour started on the 7th of August, seemingly for reasons we haven't been able to isolate.
Our current set up is that we have one primary email address that we receive all of our customer enquiries, orders, and emails through for 15+ websites. This email address is hosted through Exchange and we have set up SMTP. Our website is a WordPress based website, and we use WP Mail SMTP to connect our Exchange account to this plugin. Then, we filter this email account through MailGuard so that we mitigate 99% of the spam sent to that address.
Originally, we thought the problem was to do with this plugin, so we rolled back a version of the plugin and the issue was still not rectified. We also reached out to MailGuard asking them if they would strip Reply-To headers before they sent the email(s) back to us, and their reply from support was:
"We will add details into the headers of an email, but that will be in regards to recording the Hops of the email, whether it has passed SPF/DKIM/DMARC checks and specific logging regarding tour processing of the email.
That all being said, MailGuard's systems do not remove content from emails.
If the emails do not have a reply-to in them, that is how they are when we have received them."
As mentioned, we have 15+ other websites, but only 2 of them run through an OAuth connection with Exchange through the WP Mail SMTP plugin. The other websites, use Brevo (SendInBlue) as their SMTP provider.
Thinking it was a plugin issue, we tested the enquiries being sent from those websites to our email address, to see if they were also getting their Reply-To headers stripped, however, none of them were having this issue. We use the free SMTP service through Brevo for these smaller sites, and would exceed their limit if we switched our main sites to Brevo in the meantime.
We believe we have isolated the issue down to Exchange/Office365, but admittedly, are finding it a bit of a challenge given the intricate settings and options available throughout the account.
Below is a screenshot of two enquiries sent through to our email address, but 24 hours apart. The left indicates the the Reply-To header is present as normal, but the right image, indicates a missing Reply-To header.
To add a note, it is interesting saying that the emails were not signed. We definitely have DMARC/DKIM DNS records present so I'm unsure why they would be being delivered as unsigned.
We have not changed any SMTP settings, any policy settings, mail rules or anything similar in our Exchange account. It seemingly appears to be an issue that randomly appeared overnight.
Has anyone experienced similar issues with "Reply-To" headers being stripped in Office 365? Could there be specific settings or policies in Exchange Online or Azure that might affect this behaviour? Any advice or troubleshooting tips would be greatly appreciated.
Thank you in advance for your help.
slatediscounts
Yes we have the same problem, starting a few days ago where the reply to" email address usually found in the email headers is now missing.
Previous to this bug we were successfully using the "Post SMTP" plugin with the additional paid plugin "Office 365 for Post SMTP Extension". Today, after not being able to source the problem, we swapped to "Easy WP SMTP Pro" (paid) and the problem is still occurring.
We therefore believe this is a bug in the Microsoft Office 365 API and would appreciate a fix please.It is definitely a problem with anything going through 365/Exchange for SMTP. As I mentioned in my previous post, we have other sites running through a different SMTP provider with no issues so we may have to consider swapping over to them until this is fixed.
Hope you can find a solution in the meantime as well.
slatediscounts Thank you. Do you mind if I ask which other SMTP provider you use? I use Sendgrid/Twilio a lot for non-O365 clients and have found it reliable (and free) but fairly time consuming to setup plus the 2FA is annoying.
slatediscounts We are also experiencing this issue. Its affecting our CRM as it uses the reply to address to populate contact information.
Hoping for a fix soon. In the mean time we are having to use SMTP relay with Office 365 which has multiple draw backs.
- Yep. We don't really want to use the alternative SMTP provider but we may have to until this is fixed unfortunately.
Hope it gets fixed soon for all of our sakes.
- Having this issue too, severely impacting our workflow. Hoping for a fix.
- yes, I'm seeing the same issue. How do we reach out to Microsoft to get this fixed?
slatediscounts We are seeing the same problem on our Wordpress site.
- Having this issue too since August 7th on WordPress site using WP Mail SMTP. Hoping for a fix soon from Microsoft.
Within WP Mail SMTP plug in, i switched from 365/Outlook (free/included) to SendLayer ($180/year) and seems to be working fine for now.
- Would also love to find a solution to this, has started happening recently for me.
- If this is a policy change on Office365, has anyone found any blog/article announcing this change?
- I have the same issue. All used to work well, nothing changed in the WP SMTP setup or in the Office365 settings, and all of a sudden the Reply-To headers don't appear anymore.
In the email log in Easy WP SMTP the header is still there, but it's not present in the email I receive. - Found the following over here:
https://support.nhs.net/2024/08/microsoft-365-alert-service-degradation-microsoft-intune-some-users-microsoft-power-automate-workflows-with-email-replies-configured-may-be-unable-to-send-email-messa/
See also:
https://learn.microsoft.com/en-us/answers/questions/1855228/graph-api-replyto-not-set-when-sending-e-mails
I'm hoping it is relevant for you folks:
Microsoft Reference: MF860777
Issue Status: OPEN
Issue Description: Users Microsoft Power Automate workflows with email replies configured may be unable to send email messages.
More info: This issue is specific to workflows that leverage Microsoft Graph API and use reply To in the /send Mail function.
Current Update: 14/08/2024 09:06:00 AM – Microsoft have developed a code fix to address the specific portion of offending code within the recent update, which is undergoing testing and validation to ensure it will resolve the impact. Once this process is complete, they will begin deploying it to the affected environments. They expect the fix will take one week to reach full saturation in the affected environments.
Scope of impact: Some users Microsoft Power Automate workflows with email replies configured that leverage Microsoft Graph API and use reply To in the/send Mail function may be impacted.
Root cause: A recent service update to Microsoft Graph API contains a code regression that is preventing the /reply To feature from functioning properly and resulting in impact.jimpotter-trgscreenthank you for sharing the update. We too are affected by this, started 8/2. Wordpress, Woocommerce, WP Mail SMTP via Azure API.
- Thanks Jim. It seems to be fixed for us now, so hopefully it's been patched up for all the other folks in this thread.
jimpotter-trgscreen thanks! It's fixed now for us
