Using SMTP on a Function App API

Ho, Keith D 120

When I run the code below through that's on my API call, the code stops at the smtp_connection part. I'm able to run the API locally but when it is deployed on the Function App, it doesn't run through the smtp_connection line. Are there any settings I need to set up to allow this to go through?

        smtp_server = os.getenv("SMTP_SERVER")  
        smtp_port = 25  
        smtp_connection = smtplib.SMTP(smtp_server, smtp_port)

Ho, Keith D 120 Reputation points

2024-11-07T21:17:59.1433333+00:00

Note: This code is in Python
KarishmaTiwari-MSFT 20,207 Reputation points Microsoft Employee

2024-11-08T01:38:40.0166667+00:00

@Ho, Keith D Thanks for posting your query on Microsoft Q&A. Our team is looking into this and will get back shortly.
JananiRamesh-MSFT 27,911 Reputation points

2024-11-08T05:17:13.2033333+00:00

@Ho, Keith D Thanks for reaching out. The preferred way to send e-mail from within Azure is through an SMTP relay service like the SendGrid Output binding: Azure Functions SendGrid bindings | Microsoft Learn , rather than sending e-mail directly from Azure Functions/ VMs etc

Sending email on Port 25 is unsupported from all Azure Platform-as-a-Service (PaaS) resources, including Azure App Service and Azure Functions and it is blocked with most subscriptions

please review this article for more information: Troubleshoot outbound SMTP connectivity in Azure | Microsoft Learn.

do let me know incase of further queries, I would be happy to assist you.

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Using SMTP on a Function App API

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