SMTP Error 250 is an indication that the SMTP client encountered authentication issues, usually stemming from invalid user credentials or misconfigurations within the client.

What's Causing This SMTP Error 250:

The SMTP Error 250 is commonly caused by:

1. Invalid user credentials.
2. Misconfigurations within the SMTP client.

How SMTP Error 250 Manifests in Different Environments:

SMTP Error 250 in phpmailer:

• Case 1: "SMTP Error 250 - Authentication failure due to invalid user credentials in phpmailer."
• Case 2: "SMTP Error 250 - Misconfigurations in the SMTP client in phpmailer."

SMTP Error 250 in Jenkins:

• Case 1: "SMTP Error 250 - Authentication failure due to invalid user credentials in Jenkins."
• Case 2: "SMTP Error 250 - Misconfigurations in the SMTP client in Jenkins."

How to Resolve SMTP Error 250 - Step-by-Step Solution:

To address SMTP Error 250, focus on the following parameters:

1. SMTP TLS Protocols: Ensure that the TLS protocols configured in your SMTP client align with the requirements of the email server.
2. SMTP TLS Ciphers: Verify that the TLS ciphers used by the SMTP client match the server's specifications.
3. User Credentials Validation: Confirm the validity of user credentials to ensure acceptance by the email server.

By meticulously addressing these parameters, you can effectively resolve SMTP Error 250 in both phpmailer and Jenkins environments.