Error: "Client host [smtp1.infomaniak.ch] blocked using Barracuda Reputation"

Occasionally when you attempt to send a message, you may receive a return error message warning you that your address has been blacklisted in some way:

----- The following addresses had permanent fatal errors -----
<recipient@domain.xyz>
(reason: 554 Service unavailable;
Client host [smtp1.infomaniak.ch] blocked using Barracuda Reputation;
http://bbl.barracudacentral.com/q.cgi?ip=xx.xx.xx.xx)

This message informs you that the destination mail server (where your recipient is located) is refusing your messages on the basis of their source: for example the dynamic, temporary IP address assigned to you by your Internet Service Provider.

The organisations that maintain these blacklists do so in order to restrict the volume of spam sent over the Internet.

The IP addresses logged on one of these servers may have been the source of spamming and the cause of multiple complaints.

This means that the Internet Service Provider responsible for these IP addresses has not acted accordingly, for instance by not properly configuring its mail servers.

All such lists have tools for administering them and removing any addresses that have no reason to be there (where the situation has been rectified, mail servers correctly configured, etc). But you, as a user, can almost never do anything about it yourself.

Only the administrator of your network or the list that rejected you can take action.

There are several ways to resolve this issue:

• you may disconnect and re-connect (by unplugging your modem then plugging it back in), which will usually mean that you are assigned a new IP address.
• you may also follow the procedure given by the organisation that blacklisted you (e.g. http://www.barracudacentral.org/ ) to make sure that your current address is erased from the list concerned.
• you could potentially switch ISP