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SMTP error codes

Mail servers produce Simple Mail Transfer Protocol (SMTP) codes in response to transaction requests. Some of these response codes indicate errors.

You may see the following errors:

Error code Description
XGEMAIL_0001 Message didn't contain a valid DKIM signature.
XGEMAIL_0002 Message failed a SPF check.
XGEMAIL_0003 Message failed a DMARC check.
XGEMAIL_0004 Sender IP address failed a RBL test.
XGEMAIL_0005 Sender domain failed a DBL test.
XGEMAIL_0006 Message rejected because the TLS version used doesn't match the version configured in your policy.
XGEMAIL_0007 Message rejected because your license has expired.
XGEMAIL_0008 Message rejected because a domain, an IP address, or an email address is in the admin block list.
XGEMAIL_0009 Message rejected because a domain, an IP address, or an email address is in the user block list.
XGEMAIL_0010 Message rejected because the recipient's domain isn't a Sophos Email protected domain.
XGEMAIL_0011 Message rejected because the recipient's email address doesn't exist in the Sophos Email protected domain.