Basic Authentication Deprecation in Exchange Online

As of October 1, 2022, Microsoft begins to permanently disable Basic Auth in all tenants, regardless of usage, with the exception of SMTP AUTH.

Situation

You, or your MBS (Managed Backup Service) customers, do not receive email notifications regarding the results of backup or restore plans and you have a custom SMTP Email Service ( Microsoft 365).

Cause

Such issues might be caused by deprecation of Basic Authentication, as announced by Microsoft.

Solution

You should change your Email Service Settings to avoid the issue. Use one of the following options:

Use MSP360 Email Service To use the MSP360 email service, proceed as follows:
1. Open the Management Console.
2. In the Settings menu, select Email Service.
3. Select MSP360.
4. Specify the required email address, then click Verify.
Use another custom SMTP service, e.g., Amazon SES To use the Amazon SES email service, proceed as follows:
1. Open the Management Console.
2. In the Settings menu, select Email Service.
3. Select Amazon SES.
4. Proceed with the steps provided for the Amazon SES email service:
  - Verify your email. Click Verify Email, then wait until your email address is verified
  - Request production access. Once your email address is verified, your SES account is put into a sandbox. While your Amazon SES account is in the sandbox, several restrictions are applied:
  - You can only send mail to verified email addresses and domains, or the Amazon SES mailbox simulator
  - You can only send mail from verified email addresses and domains
  - You can send a maximum of 200 messages per 24-hour period
  - You can send a maximum of 1 message per second
To request that your account be removed from the Amazon SES sandbox using the AWS Management Console, proceed with the instructions in the Moving out of the Amazon SES sandbox chapter at docs.aws.amazon.com
1. Send a test email through SES to the specified email address.
2. Once you are done, click Save Changes.