3-digit reply code Success

SMTP error 235

Authentication successful.

Updated Jul 1, 2026

The short answer

Authentication successful. Common cause: Your AUTH login was accepted.

Quick fix

You are logged in and can send.

2 - Success. Not an error - the server accepted or completed the action.

How to fix it

You are logged in and can send.

Related codes

211 System status or help reply. 214 Help reply. 220 Service ready. 221 Service closing transmission channel. 250 Requested action completed. 251 User not local; will forward.
All SMTP error codes
Ready when you are

Most rejections come back to sender reputation.

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