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 […]
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. […]
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 […]
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 […]
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, […]
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 […]
Description: Cannot open connection. What does this mean? Your email (SMTP) server is unable to start an SMTP session. Typical replies will be “SMTP Error 101, Error opening connection” or “SMTP Error 101, cannot open SMTP stream”. All SMTP Error 101 errors usually point to a configuration problem, such as an incorrectly spelled SMTP server, […]
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 […]
Description: Command parameter not implemented. What does this mean? This is another name or reference for SMTP Error # 502. Please reference it’s documentation. Related Articles: SMTP Error 214 SMTP Error 421 SMTP Error 450 SMTP Error 503 SMTP Error 541
Description: Invalid email address. What does this mean? This response is straight forward. One of the email addresses in the ‘TO:’, ‘CC:’, or ‘BCC:’ is incorrect (invalid). How to fix SMTP Error 510? Check all email addresses in your message, including (‘TO:’, ‘CC:’, and/or ‘BCC:’), for any misspelling. Related Articles: SMTP Error 214 SMTP Error […]