Error when updating SMTP credentials in Terraform enterprise

Problem

Error when updating SMTP credentials in Terraform Enterprise:
Error saving SMTP settings Delivery Test Error

Prerequisites

• Your instance is making use of AWS IAM credentials and attempting to interact with an AWS SMTP server.
• Check for a more descriptive error in the ptfe_sidekiq(for Terraform Enterprise v202205-1 and later tfe-atlas) container docker logs by following the steps in this knowledge-base article.
• If no errors are seen by following the steps in the article, the error may be related to your AWS credentials.

Solutions:

• The error may be related to a user's IAM secret access key was being used instead of their SMTP password.
  • Please ensure that the correct SMTP password is being used by following this guide from AWS:
    https://docs.aws.amazon.com/ses/latest/DeveloperGuide/smtp-credentials.html

Additional Information

• If the error found by the command is not solved by the process above, please open a ticket with Hashicorp Support.