SMTP error in Outlook.com

SMTP errors can occur when a user tries to send a Hotmail, Gmail or Yahoo! Mail e-mail in Outlook.com.

These situations can be inconvenient to the user, as most SMTP errors arise with the message that the email can not be sent to the recipient. Therefore, it is important to know some SMTP errors that may affect Outlook and Outlook.com users.

Outlook SMTP error

Many of the errors outlined here also show compatibility with other e-mail services and what they mean:

  • 421 RP-001: The limits allowed by the server have been exceeded.
  • 421 RP-002: The limits allowed by the server for the connection process are being exceeded.
  • 421 RP-003: The number of connections allowed has been exceeded.
  • 550 SC-001: Email rejected by Outlook.com due to existing policies (usually due to email content).
  • 550 SC-002: E-mail rejected due to suspicious activity on the server.
  • 550 SC-003: Email rejected due to its policy, usually due to a problem using the proxy.
  • 550 SC-004: email rejected due to the fact that our ip is blocked. This type of lock may arise from other user complaints or automated systems.
  • 550 DY-001: email blocked by ip origin.
  • 550 DY-002: Block email viruses on servers or PCs.
  • 550 OU-001: The message was denied because it was blocked at spamhaus.org.
  • 550 OU-002: message rejected because of its contents.

All SMTP errors in Outlook.com may appear to users when you are sending an email. In addition to Outlook.com, they can still appear on various email clients, such as Outlook, Thunderbird and more.

Here are some SMTP errors, but to solve them, users must have advanced knowledge about the server and especially the e-mail service. Using the help provided by Microsoft is often helpful in finding a solution to this kind of error.

Read more: How to recover drafts in Outlook for Android.