IP Address is DUL help

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ASKER

When you say 'check' these sites? could you explain in more detail please ?

the links mentioned above have information as to why the error is coming and how to resolve it. the NDR comes when the ip address has been blocked and the same is mentioned in the above links.

ASKER

Ok so if i get the users ip and use the Lookup Tool on that website ? it should report back its being blocked ? and then if i submit thier IP to mail-abuse.com they will remove it from the list ?

yes

ASKER

Hmm one more point, the user seems to be albe to send mail to other addresses at our domain just seems like its one address here hes trying to send to it wont let him

the NDR that he is getting points to his IP being blocked by/at mail-abuse.com
try doing a lookup to see if the ip is blocked. if it is blocked then you can request a release or ask the sender to request the release.

mattash55 - do you use Messagelabs? ML allow customers to customise their anti-spam options, including using DUL, via a secure web control panel. This is not on by default.

ASKER

Yes we use message labs here

ASKER

Could you step me through the proccess ?

I can't give you a walkthrough as I don't have a logon to ML. However, according to a current ML user guide you should logon to Messagelabs using the URL, username and password that they supplied to your company. Then disable "Use public block list DUL (Dynamic User List)" from the "Detection Settings" tab.

See http://www.messagelabs.com/Utilities/Support/Support/ML_has_blocked_my_message to confirm that 553-mail rejected because your IP is in DUL can indicate that ML is blocking inbound mail from the specific sender.

I believe that the URL you need is https://clients.messagelabs.com. You may choose to add the blocked sender via the "Approved Senders" tab rather than disabling DUL.

ML recommended AS settings (Best Practice) were:

-Blocked Senders list (IP) - set to Block and Delete
-Blocked Senders list (Domain) - set to Block and Delete
-ORDB - set to Append A Header and Redirect to Bulk Mail Address (Do NOT Block/Delete)
-RBL - set to Append A Header and Redirect to Bulk Mail Address (Do NOT Block/Delete)
-RSS - set to Append A Header and Redirect to Bulk Mail Address (Do NOT Block/Delete)
-DUL - set to Block and Delete
-Signature System - set to Block and Delete
-Skeptic Heuristic - set to Append A Header and Redirect to Bulk Mail Address (Do NOT Block/Delete)

ASKER

Ok thats great ! the only guy that knows our message labs login is off today so i`ll try it tommorow thanks again ! The error message they get doesnt seem to be listen though but im guessing it comes under '533 your ip is listed it' :/ if thats so i guess theres nothing we can do bar advise them

Sembee

Just to point out - if an IP address is being reported to be in DUL, then the chances of getting de-listed from that list is practically nil. DUL is Dial up List - basically a dynamic assigned IP address. The blacklist operators will tell you that the list of IP addresses was supplied to them by your ISP. They cannot (and will not) remove a single IP address from the list as the list is a subnet, not individual IP addresses.

If the sender has paid for a static IP address then they need to speak to their ISP and get a new address that isn't in the Dynamic IP range.
If the sender is using a server on a dynamic IP address, then they only have themselves to blame. They either need to get a static IP address or route their outbound email through the ISPs SMTP Server.

Simon.