XMission Mail Rejection Codes

If mail you're trying to send to XMission is getting bounced, this is the place too look for help.

Our incoming mail servers are configured to reject mail under a number of circumstances to keep our mail system running smoothly and to reduce spam. Each rejection has a numeric code to describe the reason for rejecting a particular piece of mail. The rejections look like this:

550-XM-RJCT01: Account <thisisjustatestdude@xmission.com> does not exist.
550 [166.70.13.211] [mx01.mta.xmission.com]

In this case, it's XM-RJCT01, which indicates that an email's destination address doesn't exist. For your convenience, here is a list of all our custom reject codes.

XM-RJCT01: Invalid Username

This means that the address being sent to does not exist. This reject code is only given to @xmission.com email addresses.

XM-RJCT02: Invalid Virtual Mail Recipient

This reject code also means that the address being sent to does not exist, but it's given when the recipient domain is hosted with us under our "Virtual Mail" system.

XM-RJCT03: IP Address is listed in XMORTS

XM-RJCT03 indicates that the IP address attempting to send the message to our servers is known to be an open relay. If you are getting this reject code, you should reconfigure your machine so it no longer functions as an open relay. Once you do this, you will be aged out of the system. If you have any questions, please call our technical support.

XM-RJCT04: IP address listed in SBL

This indicates that the IP address connecting to our machines is listed in Spamhaus's SBL blocklist. Please contact Spamhaus to be removed from the SBL.

XM-RJCT05: IP address listed in XBL

This indicates that the IP address connecting to our machines is listed in Spamhaus's XBL blocklist. Please contact Spamhaus to be removed from the SBL.

XM-RJCT06: Unauthorized relay attempt

This means that the address being sent to is not a domain that our mail systems are configured to handle, and that the sender is not authorized to relay mail to other systems. If you have an XMission account and are connecting from off of our network, you need to use SMTP authentication to send mail to non-XMission addresses. If you're attempting to send mail to a legitimate domain through your own mail system, there is probably some discrepancy with their DNS record between your system and ours. Either contact the owner of the domain, or contact our technical support.

XM-RJCT07: User listed in rcpt-rbl DEFUNCT

**No longer a valid RJCT code** This is an RBL we ran that would blacklist ips based on how many attempts at sending to invalid recipients came from the IP. This was intended to prevent dictionary attacks, but it is now defunct. There are currently a few IPs that will age out of the system by the end of September, most of which are already listed on the Spamhaus PBL. If you do manage to encounter this reject code, please contact our technical support.

XM-RJCT08: Invalid "Spamcatcher" recipient

This means that the recipient does not exist and is on a domain using our SMTP Spam Filtering ("spamcatcher") service. We check this by directly contacting a mail server run by the owner of the recipient domain. Please contact the owner of the domain or email account you are attempting to send to.

XM-RJCT09: SPF Record Fail (ETRN)

This means that the sender address (provided on the SMTP "MAIL FROM" line) is rejected by the SPF record of it's domain. There is some problem with your SPF record. This message only occurs when sending to domains we relay mail for. If you are forwarding mail from an account to one of these domains, please contact our technical support and ask for an SPF exemption, as SPF is incompatible with the forwarding mechanisms on many mail servers.

XM-RJCT10: Mail failed virus scan

RJCT10 means that our virus scanner (ClamAV) detected a virus somewhere in the body of the message. This almost certainly means that there really was a virus in your message. Check your attachments for viruses, or, if you didn't intentionally attach anything, check your system for viruses and spyware. If you feel you have encountered a false positive, please contact our technical support.

XM-RJCT11: Internal

This reject code exists, but is used for internal purposes. If you encounter it somehow, please contact technical support.

XM-RJCT12: Known Phishing Address

This code is reserved for email addresses known to be owned by phishers. The addresses are manually added by our admins after an email is flagged as phishing. If you are receiving a bounceback email with this code and know for certain that the recipient is not a phisher, please contact XMission's techinical support staff.

XM-RJCT13: Forged sender address

This code only occurs when somebody attempts to forge an email address used for administrative purposes at XMission (ie support@xmission.com). Please don't do that. :)

XM-RJCT14: Botnet RBL DEFUNCT

**No longer a valid RJCT code** This means that the IP address attempting to send to us is on our XMission Botnet RBL. There is further information and an interface for removal/whitelisting here.

XM-RJCT15: User in OPS blacklist

This means that we've manually blocked the sending server's ip address. This generally means that the IP address came to our attention because it was causing some sort of problem. Please contact our technical support.

XM-RJCT16: SPF Failure

This means that the sender address (provided on the SMTP "MAIL FROM" line) is rejected by the SPF record of it's domain. There is some problem with your SPF record. If you are forwarding mail from an account to XMission, please contact our technical support and ask for an SPF exemption, as SPF is incompatible with the forwarding mechanisms on many mail servers.

XM-RJCT17: DomainKey Failure

This means that the sender address (provided on the SMTP "MAIL FROM" line) is rejected by the DomainKey of it's domain. There is some problem with your DomainKey.

XM-RJCT18: High SpamAssassin Score DEFUNCT

**No longer a valid RJCT code** RJCT18 occurs when the message receives an extremely high score by SpamAssassin. If the message you're attempting to send isn't spam, please contact our technical support.

XM-RJCT19: IP address listed in PBL

This indicates that the IP address connecting to our machines is listed in Spamhaus's PBL blocklist. Please contact Spamhaus to be removed from the SBL.

XM-RJCT20: Invalid Zimbra Recipient

This means that the recipient doesn't exist and is on a domain hosted on our Zimbra hosting package. Please check for typos or contact the person you were attempting to send email to.

XM-RJCT21: Domain has no hosting

RJCT21 means that the recipient domain has XMission in their MX record, but has not purchased or configured any sort of email hosting package. The owner of the domain needs to either update their MX record or set up an email hosting package.

XM-RJCT22: IP listed in XMission RBL

This means that the IP address attempting to send to us is in the XMission General RBL. There is further information and an interface for removal/whitelisting here.