Whylidate
Permanent FailureHigh Severity

SMTP Error 550 5.2.1

Mailbox Disabled

The recipient's mailbox has been disabled or suspended.

What This Error Means

The email account exists but has been disabled by the administrator or the email provider. This could be due to inactivity, policy violations, or account suspension.

Common Causes

  • 1Account suspended for policy violations
  • 2Mailbox disabled due to inactivity
  • 3Organization disabled the user's account
  • 4Account pending deletion

How to Fix It

  • 1Remove the address from your mailing list
  • 2Contact the recipient through other means
  • 3Use email verification to detect disabled accounts
  • 4Implement regular list cleaning

Prevention with Whylidate

Prevent this error before it happens by validating email addresses with Whylidate. Our real-time verification catches invalid addresses, full mailboxes, and policy issues before you send.

Quick Reference

Error Code
550 5.2.1
Category
Permanent Failure
Severity
High
Should Retry?
No

Related Errors

View All SMTP Errors