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Blacklist error message

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  • Last reply by lawoffice4

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Thunderbird was sending and receiving just fine until a couple hours ago. Now, I cannot send anything to anyone - including my email provider. The message is: "Outgoing server (SMTP) error. The server responded: (C18) RBL restriction: Blacklisted by Internal Reputation Service" I verified all the settings (though I changed nothing prior to the problem) and all is correct. I've checked with tech' support and they verified that my address does not have a Blacklist. I've restarted the program and restarted the computer. I've also donated several times to Thunderbird. Before I change clients, I thought I'd see if anyone had a fix for this. Thanks, D

Thunderbird was sending and receiving just fine until a couple hours ago. Now, I cannot send anything to anyone - including my email provider. The message is: "Outgoing server (SMTP) error. The server responded: (C18) RBL restriction: Blacklisted by Internal Reputation Service" I verified all the settings (though I changed nothing prior to the problem) and all is correct. I've checked with tech' support and they verified that my address does not have a Blacklist. I've restarted the program and restarted the computer. I've also donated several times to Thunderbird. Before I change clients, I thought I'd see if anyone had a fix for this. Thanks, D

All Replies (3)

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And 'Yes' - I can send using webmail services.

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The fact that you can send via webmail isn't necessarily relevant because it probably doesn't send and receive through the same servers that IMAP/POP3/SMTP use.

As far as I can tell from some web research, that error message does indicate that you are blacklisted by your email service, despite what they are telling you. You may have to press their tech support people to follow up on this.

I do not think this is a Thunderbird issue. I suspect that, if as a test, you were to install another local mail program with the same settings, you would get the same or similar error.

Google "email blacklist check" will find a number of sites that can see if your IP or domain is listed in some common blacklist databases.

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Well, surprise surprise - the problem resolved itself. I am once again able to send messages. I have no idea why or what changed but it was none of my doing. My only guess is that some algorithm flagged my IP for one reason or another. Solution for others? Give it 24 hours I guess. Thanks Lin for looking into it for me. David

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