Server busy. Please try again later from ip

Question

hello,

I represent the abuse team of Topnet Tunisia internet service provider.

we have a problem sending emails to outlook servers with the error message:

dutexlautexconfection-com02i.mail.protection.outlook.com[52.101.73.2] said: 451 4.7.500 Server busy. Please try again later from [41.226.16.68]

ericsson-com.mail.protection.outlook.com[52.101.73.30] said: 451 4.7.500 Server busy. Please try again later from [41.226.16.62

Our MTA IPs are not blacklisted but outlook server reject our mail, ip list:

41.226.16.68

41.226.16.62

41.226.16.63

41.226.16.64 and 41.226.16.67

Please check to unblock our mta's emails.

THANKS

Sincerely

Answer 1

we cannot send our emails to several Outlook users from our SMTP relays

error message :tunisietelecom.tn>, relay=tunisietelecom-tn.mail.protection.outlook.com[52.101.68.27]:25, delay=2.5, delays=0.04/0/1.8/0.64, dsn=4.7.500, status=deferred (host tunisietelecom-tn.mail.protection.outlook.com[52.101.68.27] said: 451 4.7.500 Server busy. Please try again later from [41.226.16.64