Revised 06/26/2026
As of early 2026, akoyaGO has observed an increase in email deliverability issues when emails are sent from onmicrosoft.com addresses. Although emails appear to send successfully within akoyaGO, many recipient organizations are now automatically flagging or blocking messages from onmicrosoft.com domains as spam, a behavior controlled entirely by the recipient’s email provider and outside of akoyaGO’s control. While these emails may have previously been delivered without issue, evolving security standards and increasingly strict spam‑filtering rules have led to more aggressive filtering of onmicrosoft.com domains, resulting in a higher rate of messages being blocked, marked as undeliverable, or flagged as spam. This trend has been consistently observed across multiple client environments utilizing onmicrosoft.com addresses for automated emails from GOapply, GOfund, and GOdonate. In these cases, emails will show as successfully sent within akoyaGO but may still be rejected or filtered by receiving servers due to domain authentication limitations and spam‑filtering policies; certain providers, such as iCloud, are particularly strict and may automatically treat these messages as untrusted. Organizations currently using onmicrosoft.com addresses for automated emails should review akoyaGO’s recommended best practices to improve deliverability.
Recommendation - Long Term
To avoid ongoing email delivery issues, we strongly recommend using a dedicated, custom domain for sending automated emails, rather than an onmicrosoft.com address. As long as onmicrosoft.com remains the sending domain, emails may continue to be blocked or filtered by recipient email providers.
Option 1: Bring an Existing Custom Domain into Microsoft (Recommended)
We recommend bringing your organization’s existing custom domain into Microsoft. This is a technical process, and the complexity depends on domain ownership:
If the domain is already managed by Microsoft, the process is generally straightforward.
If the domain is managed by another provider, the setup can be more complex and may require changes to the email configuration. While clients can complete this process independently, we strongly recommend working with an IT firm when the domain is not Microsoft‑owned. Upon request, akoyaGO can share a trusted consulting resource who can assist with this setup.
Option 2: Add a New Custom Domain to Your Tenant
If bringing an existing domain into Microsoft is not an option, an alternative is to add a new custom domain to your tenant that uses a domain name other than onmicrosoft.com and configure automated emails to send from that domain.
Microsoft documentation for adding a custom domain can be found here: https://learn.microsoft.com/en-us/microsoft-365/admin/setup/add-domain?view=o365-worldwide&tabs=domain-connect
Workaround - Short Term
If you are experiencing this issue and need a short-term workaround while a long‑term domain solution is being implemented, you can forward or manually resend the automated emails. *Please note this is not a permanent solution. Long‑term email deliverability issues will persist until automated emails are sent from a custom domain rather than an onmicrosoft.com address.
To locate the email, navigate to the Activities table, change the view to All Emails, and select the appropriate email:
Open the email activity by double‑clicking it. From there, you have two options:
- Option 1: Forward the email to the end user, ensuring the sender address is not an onmicrosoft.com address. (For example, using an address with your organization’s domain.)
- Option 2: Copy the contents of the email and paste them into a new email sent directly from your standard organizational email address.