Problem sending email to office 365 users


Active Member
Jan 15, 2021
El Salvador
cPanel Access Level
Root Administrator
Good morning

I have a VPS from where I send emails to my clients and suppliers and I am receiving an error to send to more than 2 recipients who have their emails with office 365, the error I receive is the following:
SMTP error from remote mail server after RCPT TO:<>: 452 4.5.3 Too many recipients (AS780090) [ 2023-04-21T15:46: 05.104Z 08DB4184483426D3]

All emails are legitimate and are not spam.


Jurassic Moderator
Staff member
Oct 19, 2014
cPanel Access Level
Root Administrator
Hey there! As mentioned in the other thread yesterday, it would be best to contact Microsoft directly to find out why you are being ratelimited. There aren't going to be any additional details that anyone else can provide since the email is properly leaving your server, and then be limited by the Microsoft network.