Fix a Missing Exchange Hybrid SMTP Address After the Hybrid Configuration Wizard
Question details
Determine why a migrated mailbox did not receive the tenant.mail.onmicrosoft.com SMTP proxy address after the Hybrid Configuration Wizard ran, and correct the policy or synchronization issue.
- Product
- Microsoft Exchange Server, Exchange Online, and Hybrid Configuration Wizard
- Device & OS
- not provided
- Scenario
- An administrator has configured Exchange hybrid migration and expects the on-premises email address policy to add the tenant's hybrid routing domain to eligible mailboxes.
- Observed behavior
- The migrated mailbox lacks the tenant.mail.onmicrosoft.com SMTP proxy address even though automatic email address policy updates are enabled.
Open the on-premises Exchange Management Shell with permissions to inspect and manage recipients and email address policies. Confirm the tenant's actual hybrid routing domain, such as contoso.mail.onmicrosoft.com, and identify the affected recipient and the Microsoft Entra Connect Sync server.
Identify whether the missing address originates in the hybrid wizard or the email address policy
Start here to establish whether the policy contains the routing domain and whether it applies to the affected recipient.
An enabled email address policy setting does not prove that the correct policy matches the recipient or contains the required address template. The missing address alone also does not establish why the Hybrid Configuration Wizard failed; its logs are needed to investigate that question.
On the computer and user profile used to run the Hybrid Configuration Wizard, open File Explorer and enter %UserProfile%\AppData\Roaming\Microsoft\Exchange Hybrid Configuration. Review the logs for the relevant run and look for email address policy errors, failed configuration tasks, or permission failures.
In the on-premises Exchange Management Shell, run Get-Mailbox <AffectedUser> | Format-List EmailAddresses,EmailAddressPolicyEnabled. Replace <AffectedUser> with the mailbox identity. If the migrated recipient is now represented as a remote mailbox, run Get-RemoteMailbox <AffectedUser> | Format-List EmailAddresses,EmailAddressPolicyEnabled,RemoteRoutingAddress instead. Check whether the tenant.mail.onmicrosoft.com proxy is present.
Run Get-EmailAddressPolicy | Format-List Identity,Priority,RecipientFilter,EnabledEmailAddressTemplates. Verify that the policy matching the affected recipient includes a secondary SMTP template for the actual hybrid routing domain, such as smtp:%m@contoso.mail.onmicrosoft.com. Check policy priority and recipient filters rather than assuming the default policy applies.
Correct and apply the on-premises email address policy
Use this when the applicable policy is missing the hybrid routing domain template or has not stamped the address on eligible recipients.
Synchronize the corrected SMTP proxy address to Exchange Online
Use this when the address exists on-premises but is still missing from the cloud mailbox.
Document Your Exchange Migration Checks with WPS Office
WPS Office does not repair Exchange hybrid configuration or directory synchronization. For migration checklists, troubleshooting notes, and status reports, it offers a free, lightweight Office alternative with a familiar interface and Microsoft Office format compatibility for easy migration of your documents.
Frequently Asked Questions
Why is the hybrid SMTP proxy missing even though email address policy updates are enabled?
EmailAddressPolicyEnabled only allows policy-based updates; it does not confirm that the matching policy includes the hybrid routing domain or has been applied. Run Get-EmailAddressPolicy | Format-List Identity,Priority,RecipientFilter,EnabledEmailAddressTemplates, then check the recipient's EmailAddresses. If the address exists on-premises but not online, investigate directory synchronization.
How can I determine why the Hybrid Configuration Wizard did not update the policy?
Review the logs for the relevant wizard run under %UserProfile%\AppData\Roaming\Microsoft\Exchange Hybrid Configuration on the computer where it ran. Look for policy-related tasks, errors, and permission failures. The missing proxy address by itself cannot identify the wizard's failure cause.
Should I use Get-Mailbox or Get-RemoteMailbox for the migrated user?
Use Get-Mailbox for a mailbox hosted on-premises. If the on-premises object represents a mailbox hosted in Exchange Online, use Get-RemoteMailbox in the on-premises Exchange Management Shell. To inspect the actual cloud mailbox, connect to Exchange Online PowerShell and use Get-Mailbox there.
Is tenant.onmicrosoft.com the same as tenant.mail.onmicrosoft.com?
No. They are different domains. Exchange hybrid configurations commonly use tenant.mail.onmicrosoft.com as the remote routing domain. Confirm your tenant's actual hybrid routing domain before adding a policy template; do not substitute the initial tenant.onmicrosoft.com domain.
Will forcing directory synchronization create an address that is missing on-premises?
No. A delta synchronization transfers eligible directory changes; it does not create a missing email address policy template or apply an Exchange policy. First correct and apply the on-premises policy, verify the proxy address, and then run Start-ADSyncSyncCycle -PolicyType Delta on the Entra Connect Sync server if needed.
