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SMTP Response 220

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Description: <SERVER> Service ready. What does this mean? This is a general reply advising that the SMTP server is ready to proceed with the next command. There is not a “fix” for this SMTP Response code, at this point the SMTP server is ready to continue successfully. Related Articles: SMTP Response 252 SMTP Error 446 […]

SMTP Response 221

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Description: <SERVER> Service closing transmission channel What does this mean? This response is stating the the session or connection to the mail server is now ending. Suggesting that all processes have completed, this could be successful or due to failures. SMTP Error 221 Examples There is not a “fix” for this SMTP Response code, as […]

SMTP Response 250

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Description: Requested mail action okay, completed. What does this mean? Fantastic! Your email message was delivered, as expected. This is the polar opposite of an error. There is not a “fix” for this SMTP Response code, as it’s not specifically an error. Related Articles: SMTP Response 220 SMTP Error 432 SMTP Error 452 SMTP Error […]

SMTP Error 111

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Description: Connection refused or inability to open an SMTP stream. What does this mean? This error is typically referencing a connection issue to the remove SMTP/Mail server. Often in relation to firewalls or misspelled domains. How to fix SMTP Error 111? As in most cases, you’ll want to ensure that the email address being sent […]

SMTP Error 211

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Description: System status message or system help reply. What does this mean? This is a response from the server replying with system help information regarding to your query. There is not a “fix” for this SMTP Response code, as it’s not specifically an error. Related Articles: SMTP Error 101 SMTP Error 447 SMTP Error 501 […]

SMTP Error 214

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Description: Help message (Information on non-standard command). What does this mean? This response should also contain information specific to your server. Most commonly also include a link/URL for a FAQ page. There is not a “fix” for this SMTP Response code, however the error may provide a link for more details. Related Articles: SMTP Response […]

SMTP Error 552

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Description: Requested mail action aborted: exceeded storage allocation. What does this mean? The recipient’s email inbox is full. Uh oh! Looks like someone doesn’t check or clean their mailbox often enough. How to fix SMTP Error 552? The user you’ve tried to email has an inbox that is full. Unfortunately, the only way to resolve […]

SMTP Error 553

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Description: Requested action not taken: mailbox name not allowed (e.g., mailbox syntax incorrect). What does this mean? The receiving mail server was not able to verify the email address. How to fix SMTP Error 553? Check to make sure all email addresses you are sending to (‘TO:’, ‘CC:’, ‘BCC:’) are correct. Related Articles: SMTP Error […]

SMTP Error 554

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Description: Transaction failed (Or, in the case of a connection-opening response, “No SMTP service here”). What does this mean? The receiving mail server will not accept your message. Typically in relation to your sending mail server being blacklisted. How to fix SMTP Error 554? Check your server’s IP for any possible blacklisting. If not blacklisted, […]

SMTP Error 555

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Description: MAIL FROM/RCPT TO parameters not recognized or not implemented. What does this mean? The outgoing mail server (your server) is not properly registering the email address used in either your FROM or TO settings. How to fix SMTP Error 555? Check your outgoing mail parameters to ensure proper “From:” address. Check the email recipient […]