Azure AD B2C – Verification Emails Not Being Received

Check your signed-in tenant’s Azure Service Health → Service issues first, because current reports indicate a possible Azure AD B2C/Entra External ID verification-email incident, while tenant-specific Service Health is the authoritative place to confirm whether your environment is affected.

1. Confirm whether this is a Microsoft service incident

1. In the Azure portal, switch to the directory and subscription associated with the B2C tenant.
2. Open Service Health → Service issues.
3. Filter by:
   • Service: Azure Active Directory B2C or Microsoft Entra External ID
   • The tenant’s applicable region
   • Active and recently Resolved events
4. Open any matching issue and record its:
   • Tracking ID
   • Start time and last update
   • Impacted services, subscriptions, or resources
   • Mitigation or workaround

Service Health contains tenant-relevant active incidents, advisories, and maintenance information ^1^. Resolved service issues remain in Health history for 90 days, and an issue’s update timeline can include mitigation and root-cause information ^2^.

There are current public reports of B2C MFA and External ID verification emails not arriving ^3^ ^4^, but those reports do not contain an accepted Microsoft resolution. They indicate a potentially broader problem, not confirmation that your tenant is included.

2. Isolate service-side delivery from recipient filtering

Since your audit logs already show successful send operations and you tested multiple providers, do not repeat those checks. Instead, collect a small comparison set:

• UTC timestamp of each attempt
• B2C policy/user-flow ID
• Application ID
• Correlation ID
• Recipient domain only—not the full email address
• Whether the message arrived, was delayed, or never arrived
• Whether repeated Send new code actions occurred

Ask the mail administrators for affected domains to check:

• Message trace
• Spam and quarantine
• Transport-rule rejection
• Sender or domain blocking
• Any delayed delivery record

A successful B2C event establishes that the identity flow reached the recorded operation; B2C audit logs cover platform activity such as authentication and token issuance, but they do not provide a recipient mail-system trace ^5^. Therefore, it does not establish that the destination provider accepted or delivered the message.

Avoid repeatedly requesting new codes while investigating delayed delivery: multiple codes arriving later can leave users attempting an older code, as seen in a similar intermittent B2C OTP case ^6^.

3. If you use custom policies

Application Insights can capture the executed user journey and let you compare successful and affected attempts by correlation ID. This feature applies to custom policies, not built-in user flows, and is in public preview ^7^.

In Application Insights → Logs, correlate a failing attempt:

traces
| where timestamp > ago(2h)
| where customDimensions.CorrelationId == "<correlation-id>"
| project timestamp, message, customDimensions
| order by timestamp asc

Do not enable DeploymentMode="Development" in production: detailed policy logs can collect claims and personal data. Production telemetry should use the production-safe configuration described in the same documentation.

4. Escalate when Service Health has no matching incident

Open Azure portal → ? → Create a support request and provide:

• Tenant and subscription references through the support form
• Incident start time and affected regions
• Correlation IDs and exact UTC timestamps
• Policy/user-flow IDs
• Affected recipient domains
• Successful versus failed comparison samples
• Service Health findings
• Recipient message-trace or quarantine findings

Do not include users’ full email addresses or verification codes in the description. Creating the request requires an appropriate subscription role such as Owner, Contributor, or Support Request Contributor; a Microsoft Entra request without a subscription requires an administrator role ^8^.

If reliable delivery diagnostics and control over the sender are a continuing requirement, Azure AD B2C also supports custom email verification through third-party providers, allowing control of the From address, templates, localization, and OTP settings ^5^. Treat that as a longer-term design option, not an immediate workaround unless already implemented.

References

1. Azure Service Health portal
2. Service issues
3. MFA emails ADb2c not working - Microsoft Q&A
4. Microsoft Entra External ID sign-up verification emails not received on ...
5. Technical and feature overview of Azure Active Directory B2C
6. Users from Asia/UK region are facing issue on Azure AD B2C Login with Email + OTP flow - Microsoft Q&A
7. Collect Azure Active Directory B2C logs with Application Insights
8. Create an Azure support request