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SMTP Error 541

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Description: The recipient address rejected your message: normally, it’s an error caused by an anti-spam filter. What does this mean? Uh oh! Your email has been flagged as spam or blocked for any number of reasons via the receiving server’s configuration. How to fix SMTP Error 541? Make sure that your server is not spamming […]

SMTP Error 550

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Description: Requested action not taken: mailbox unavailable (e.g., mailbox not found, no access, or command rejected for policy reasons). What does this mean? The destination mail server was unable to verify the email address used. This is most commonly a red flag that it’s not a valid email address, however may also mean that the […]

SMTP Error 551

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Description: User not local; please try <FORWARD PATH>. What does this mean? This is commonly used as a strategy for spam prevention. It’s stating that mail relaying is not allowed for some reason. It may be due to the email address or authentication settings used. How to fix SMTP Error 551? Ensure proper email authentication. […]

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 […]

SMTP Error 512

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Description: A DNS error: the host server for the recipient’s domain name cannot be found. What does this mean? The email recipient’s email address (user@domain.com) is using a domain name that can not be found. How to fix SMTP Error 512? This is commonly due to misspelling in the recipient’s email address such as (user@domain.coom […]

SMTP Error 513

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Description: Address type is incorrect (possibly misspelled). What does this mean? Luckily, this response is extremely straightforward. The suggestion event states, “Possibly misspelled.” How to fix SMTP Error 513? Check for email address misspelling(s). Ensure that the email address still exists. SMTP Error 513 Examples Related Articles: SMTP Response 251 SMTP Error 442 SMTP Error […]

SMTP Error 503

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Description: Bad sequence of commands. What does this mean? This is also very similar to SMTP Error # 501. The small difference in this, is due to the parameters or options being out of order from what the mail server expected. This is commonly seen when not authenticating the email account. How to fix SMTP […]