How to send Mail by outlook account by our application?

Question

Hello everyone:

We have an application software,

Customers can send emails via SMTP by filling in their account, password, and SMTP server information.

But recently, customers reported that if they use an Outlook account mailbox, the SMTP server address is smtp.office365.com, and they can no longer send emails.

Server response:

(535, b'5.7.139 Authentication unsuccessful, basic authentication is disabled. [SG2PR02CA0107.apcprd02.prod.outlook.com 2024-12-07T07:21:59.347Z 08DD165F890CD078]')

We checked the reason and found that

smtp.office365.com does not support the basic authentication method of mailboxes,

but supports oauth2.

So how should we deal with this situation?

As long as the customer fills in his Outlook mailbox account information,

My application can send emails as him.

Thank you very much, everyone

Answer 1

Hi @Developer GZ ,

Welcome to our forum!

Looks like your case is more related to Outlook.com account and your application software, right?

If so, please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. It's suggested that you could post your case in dedicated forum for Outlook.com for more professional advice.

Thanks for your understanding and support!

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