SMTP Error 250: Requested Action Completed
SMTP code 250 is the general-purpose success response used throughout the SMTP conversation. It confirms that the server accepted the previous command. You will see 250 after EHLO/HELO (listing server capabilities), after MAIL FROM (accepting the sender envelope address), after RCPT TO (accepting a recipient), and after the final dot in DATA (confirming the message was queued for delivery). Each 250 response at a different stage means something slightly different, but all indicate the command was processed without error.
Status
250 Requested Action CompletedExample
S: 220 mail.example.com ESMTP ready
C: EHLO sender.example.com
S: 250-mail.example.com
S: 250 SIZE 52428800
C: MAIL FROM:<[email protected]>
S: 250 OK
C: RCPT TO:<[email protected]>
S: 250 OK
C: DATA
S: 354 Start mail input; end with <CRLF>.<CRLF>
C: Subject: Hello
C:
C: Test message.
C: .
S: 250 2.0.0 OK queued as A1B2C3How to Troubleshoot
Walk through the full SMTP conversation
Connect manually and issue each command in sequence to see where 250 appears and where it does not. This identifies the exact point of failure in your mail flow.
openssl s_client -connect mail.example.com:587 -starttls smtp
Verify MX and SPF records
If 250 is returned for MAIL FROM but delivery still fails later, check that the sending domain has correct MX records and a valid SPF record that authorizes the sending server.
dig TXT example.com +shortCheck DNS Records
Check the queue ID in the response
The 250 response after DATA usually includes a queue ID (e.g., '250 2.0.0 OK queued as ABC123'). Use this ID to track the message through the server's mail logs if delivery does not complete.
Common Causes
EHLO/HELO accepted by server
highThe server recognized the client's greeting and responded with its capabilities (for EHLO) or a simple acknowledgment (for HELO). This is the normal second step in the SMTP handshake after the 220 banner.
Sender or recipient address accepted
highAfter MAIL FROM or RCPT TO, 250 confirms the server will accept mail from the specified sender or to the specified recipient. The server has verified the address syntax and, in many cases, confirmed the mailbox exists.
Message queued for delivery after DATA
highThe final 250 response after the message body (terminated by a lone dot on a line) confirms the server has accepted the message and queued it for delivery. The server typically includes a queue ID in this response.
RSET command acknowledged
mediumAfter a RSET command, 250 confirms the current mail transaction has been aborted and the server is ready for a new MAIL FROM. This is used when a client needs to start over without disconnecting.
Quick Diagnostics
Related Error Codes
Service Ready
The SMTP server is ready to begin a mail transaction and has announced its greeting banner.
Start Mail Input
The server is ready to receive the message body. End the message with a single dot on a line by itself.
Mailbox Unavailable / Action Not Taken
The recipient's mailbox does not exist, or the server has permanently rejected the message due to policy.
Mailbox Name Not Allowed
The email address syntax is invalid or the mailbox name violates server naming rules.
References
| Specification | Section |
|---|---|
| RFC 5321 | RFC 5321 §4.2.2 |
Frequently Asked Questions
This reference was compiled from official RFCs, protocol specifications, and hands-on troubleshooting experience. AI tools were used primarily for formatting and organizing the content on the page.