Sudden error in configuration sending email

[Coopbase]

Hello, I just encountered this problem regarding on the configuration setup yesterday. For how many months, the setting was good and no problem at all till yesterday.  What are the possible solution to this and what's the cause of this error? thanks

Configuration Setup:

 

Account name and sender email are same.

This is the error after "send this email"

[Dimitar]

Hello,

The cause for the issue could be that the SMTP authentication of your Office 365 account is not enabled. Third-party applications such as Report Server use SMTP submission to authenticate Office 365 accounts.

To enable the SMTP auth, you can refer to the Enable or disable SMTP AUTH in Exchange Online | Microsoft Learn article.

Additionally, If the email service has two-factor authentication, you may need to get an app-specific password. More information on this can be found in the Manage App Passwords | Microsoft article.

For more suggestions on how to resolve the issue, you may have a look at the following links:

• 535: 5.7.3 Authentication unsuccessful - Microsoft Community
• SMTP return 535: 5.7.3 Authentication unsuccessful Error When using - Microsoft Community
• Office 365 account error 535: 5.7.3 Authentication unsuccessful - Microsoft Community
• 5.7.3 Authentication unsuccessful during an SMTP session with - Microsoft Community

I hope that the provided information will help resolve the issue.

Regards,
Dimitar
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