DavidT Posted May 5, 2008 Share Posted May 5, 2008 I just sent the following alert to JT: I just had a message that I sent using "smtp.cesmail.net" blocked by a provider using the Barracuda Networks technology. Here's the error: 5.1.0 - Unknown address error 554-'Service unavailable; Client host [c60.cesmail.net] blocked using Barracuda Reputation; http://bbl.barracudacentral.com/q.cgi?ip=220.127.116.11' According to the Barracuda URL: The IP address 18.104.22.168 is listed in the Barracuda Reputation System as "poor" as of 05/05/08 10:43:42 PST. So I did a lookup on the OpenRBL, where there was a listing at the "LashBacks Unsubscribe Blacklist." So I tried delisting there and it said: "This IP was delisted before. To delist this IP again, please email delist[at]lashback.com with the IP address that you wish to remove from the blacklist." Also, according to the CompleteWhois RBL lookup, the IP was recently listed at TQMCube, but I think that listing expired. I did a lookup in the SpamCop reporting history and found a lot of potential backscatter hits, like this: Submitted: Friday, May 02, 2008 7:39:11 PM -0700: Delivery Status Notification (Failure) * 3078160525 ( 22.214.171.124 ) To: mailsys[at]admin.spamcop.net So, it seems that someone whose computer is permitted to use the outbound SMTP is spewing out junk that's affecting the reputation of the IP (the senderbase stats show an alarming 248% increase in the last day), and we're starting to have our messages blocked. DT Link to comment Share on other sites More sharing options...
This topic is now archived and is closed to further replies.