
Hello @Ramesh Raja,
Thank you for posting your query on Microsoft Q&A.
Based on your description, I understand that you have several email accounts configured in the application with SMTP authentication.
Microsoft MFA Enforcement on Oct 15th to all the users in the tenant will get impact to the Email accounts which are configured with SMTP Auth?
No, the Microsoft MFA enforcement will not affect any applications other than the Azure Portal, Entra portal, and Intune portal logins. This enforcement specifically applies to user logins on Azure, Entra, and Intune portals. End users accessing apps, websites, or services hosted on Azure, but not signing into the Azure portal, CLI, or PowerShell, will not be subject to this requirement from Microsoft. Authentication requirements for end users will still be determined by the app, website, or service owners.
We are using Microsoft Entra ID Free edition. Is it possible to exclude service accounts from MFA to login to our custom application authenticating with Entra ID.
Service accounts used to log into your custom application will not prompt for MFA after the enforcement begins. These accounts should function as intended without any issues. If there are any MFA policies configured for your tenant, you can exclude these service accounts from them. However, the mandatory MFA enforcement will not apply to service accounts authenticating on custom applications.
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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Thanks,
Raja Pothuraju.