Issue: Office 365 Smtp Error Data Not Accepted

The SMTP (Simple Mail Transfer Protocol) is an email communication interface that helps in the transmission of electric emails. It is a program used for sending emails to another computer based on the email addresses entered in the recipient field. It helps in exchanging emails among the users on the same or different computers, and it also fix the issue Office 365 SMTP error data not accepted.

It helps in sending messages to more than one recipient.

The composed message can include a text, voice, video, or even graphics.

It also sends messages to networks and devices that are outside the Internet.

The SMTP servers have the ability to identify themselves and also notice the communication standard that is implemented to perform.

They also have a way of handling errors, such as incorrect email addresses.

OUR SERVERS DO NOT ALLOW DIFFERENT USERNAME

The servers need the from email address and the same to be authenticated.
You can check the name and match it with the username to log in to the SMTP server.

THAT YOUR MAIL MESSAGE SIZE IS TOO LARGE

Some servers will have the option of rejecting the mails that are too large in size.
HTML bound emails, in general, are more prominent than standard text messages. You can also decrease the file size by modifying the mail by removing some attachments.

THE RECEIVER IS BLACKLISTED OR BLOCKED

Sometimes, specific email addresses are blocked and, and the server rejects your message.
The best thing is to implement all the above methods to see a solution for the Office 365 SMTP error data not accepted error is fixed.