![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(86.4, 57.00000000000001%, 18%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EKM%3C/text%3E%3C/svg%3E)
Outlook | Web | Outlook.com | Email
Sending, receiving, and organizing email in Outlook.com
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(0, 7.000000000000001%, 10%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EDB%3C/text%3E%3C/svg%3E)
Hi,
Other users have reported the same error recently. It may be a wider issue on Microsoft’s side, but I haven’t found official confirmation that Microsoft is working on a fix for this specific error.
https://support.microsoft.com/en-us/outlook/fix-ndr-error-550-5-7-515-in-outlook-com
If you received this error after sending an email, ask your email provider or IT team to check that the sending domain’s SPF, DKIM, and DMARC records are configured correctly.
If those checks pass and Outlook still rejects the messages, ask them to submit a ticket, including AS9031519 and the timestamp to Microsoft Developers: