The URL you mention states to contact them for assistance. Have you done that?

Yes, I've spent way too much time with Spectrum today. They had me change out my modem, which I did. That didn't fix the problem either. It just changed the IP address of the reported error. Spectrum told me that the problem is most likely with Thunderbird, since it's no longer supported by Mozilla. Does anyone know if that's correct? If so, what's my next best choice for a mail program?

Since changing the modem, the error message is now:"Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: impout006.msg.chrl.nc.charter.net cmsmtp 47.133.133.131 blocked. Please see https://www.spectrum.net/support/internet/understanding-email-error-codes for more information. AUP#Out-1130."

Yes, I've spent way too much phone time with Charter Spectrum this morning. They had me swap out the modem for a newer model. The error message now says:"Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: impout006.msg.chrl.nc.charter.net cmsmtp 47.133.133.131 blocked. Please see https://www.spectrum.net/support/internet/understanding-email-error-codes for more information. AUP#Out-1130." which is basically the same message with a different IP address. Spectrum mentioned that Thunderbird is no longer supported by Mozilla and that may be the problem. Is that correct? If so, what's a good mail program to switch to?

That comment about Mozilla and Thunderbird goes back approx eight years when people thought TB would die, but it remains strong and growing. You're safe with TB; my belief is it will outlast all the others.

Well, my problem seems to be a problem with Thunderbird.

"The IP address you’re trying to connect from has an issue with the Domain Name System. Spectrum requires a full circle DNS for emails to be allowed through. Verify the IP you’re connecting from, and check the IP address to ensure a reverse DNS entry exists for the IP. If the IP address is a Spectrum-provided email address, contact us." This is the error code AUP#Out-1130 explanation from Charter Spectrum.

Well, my problem seems to be a problem with Thunderbird.

No Thunderbird is reporting the error message issues by Spectrum. The error message is fairly typical is poorly configured spam filtering on the SMTP server.

The IP address they are blocking is 47.133.133.131 I did a check, and sure enough that IP address is registered to Spectrum. See https://myip.ms/view/ip_addresses/797279488/47.133.133.0_47.133.133.255 and it looks like a residential address in "kill devil hills NC" https://myip.ms/view/cities/32084/IP_Addresses_Kill_Devil_Hills.html

I checked the spamhaus project and your IP is registered there by your ISP as a residential IP. https://check.spamhaus.org/listed/?searchterm=47.133.133.131

So the issue is your provider has blocked incoming mail from it's own residential ip addresses because, well I don't know why. If I said what I thought it would not be complimentary of the skills for the individuals concerned.

The idea is "sort of sound", they could argue that they should not be receiving email to delivery from home IP addresses, but the fact they committed to exclude their own residential IP addresses is the issue.

Email not originating from their users comes to the server on Port 25, that is the universal server to server port used to communicate mail for delivery. Mail from their own users being submitted comes in on other ports and those ports should not be using the same rules that are being applied to mail from elsewhere. Apparently they are!

I would say you need to contact Spectrum. Tell the script jockey you need to speak with someone in level two support that actually understands email submission protocols and rules. This is an error resulting directly from misconfiguration of their server.

I will certainly try contacting Spectrum with your information. Thank you.

I just can't send emails:

An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: impout001.msg.chrl.nc.charter.net cmsmtp 47.132.82.220 blocked. Please see https://www.spectrum.net/support/internet/understanding-email-error-codes for more information. AUP#Out-1130.

Spectrum said its Thunderbird that's the problem.. I can logon Spectrum's website and use the email from the site and it works perfectly

bharding6340 bharding6340 Today at 9:55 AM

just don't send emails:

Sounds like you got read from the same Spectrum tech support manual that was read to me. I can also logon to Spectrum's website and use my webmail there. I can even use my gMail account through Thunderbird! I don't believe it is Thunderbird.

After another hour this afternoon with Spectrum, they did a factory reset on my new modem, and said there is absolutely nothing on their end blocking my IP address from sending emails. Their only suggestion was that my problem may be "device specific" and I should try installing Thunderbird on another device to see if that solves the problem. But if it doesn't, they have nothing else for me. I am running Thunderbird on an older desktop running Windows 10, as I have been for several years. Any thoughts on their suggestion?

The message from the spectrum server is here So really there is only one question or variable remaining. Is the connection to the internet not from Charter/Spectum

It has long been a bizarre situation where these people insist you connect to their server from their internet service to send mail. SO we are left with only one possibility. Are you connected with their service? What I tested things earlier, the IP address was a domestic one issued by them, but for anyone using a VPN, that would be hidden and could result in this error. But the reported IP address would not be a charter/Spectrum one.

As I wrote that it occurred to me that there is a second possibility. Misconfigured ports in Thunderbird. What port and server is being used to send mail according to the SMTP settings in Thunderbird.

Basically however, spectrum are the ones with the defective configuration and I have no idea how you penetrate the wall of incompetent script reader on their support lines.

I'm using the ports and protocols provided by Thunderbird for Spectrum, and verified by Spectrum at least twice. So I don't think that's the problem. I also went into the Password Manager in TB and deleted all my old passwords, which forced it to ask me to re-enter them when it restarted. No difference. Their tech support had me connect my Ethernet connection directly from their modem to my desktop, instead of running it through my router. The only difference was that the error message contained a slightly different IP address; I assume the modem's was slightly different from the router's. They have been adamant that they are not blocking my IP address. Whether they know what they're talking about is another question. Is there any chance that TB is generating the error message in error itself?

Also, in this investigating process, I have used an old modem, a new modem, and a router. I have received error messages that were identical, except for the slightly different IP addresses. Why would 3 different IP addresses be blocked?

Also, in this investigating process, I have used an old modem, a new modem, and a router. I have received error messages that were identical, except for the slightly different IP addresses. Why would 3 different IP addresses be blocked?

Because you ISP has listed ALL of their residential IP addresses as such for spam blocking. (my link to spamhaus), then invoked a stupid spam filter on their server that blocks residential IP addresses.

Just to be entirely complete here. You can log your attempt to send and see in the log the refusal message coming from the server. https://thunderbirdtweaks.blogspot.com/2021/10/logging-mail-sending-in-thunderbird.html

You can try and tend am email using the text based telnet product. If it does not work you will be setting a reply from the server in a text window, not a message. But it will prove or disprove Thunderbird's involvement. https://mediatemple.net/community/products/dv/204404584/sending-or-viewing-emails-using-telnet

Note 1 Do not use the 25 mentioned in the article, use the port your outgoing in Thunderbird is set to. Note 2 Windows does not install telnet by default so you will need to add it.

Thanks for that. It's on the extreme edge of my abilities, but I'll study it and see if I can make it work.

About 5 minutes ago, my emails started working again! Perhaps the real tech people got back after a weekend off. I never got around to trying Telnet, as today was a work day for me. I use Thunderbird of course, and had never set up Microsoft Mail because of it. I thought that if Spectrum were truly blocking my IP address, then I wouldn't be able to send from it either. So I set up an account through Microsoft Mail and tried. Interestingly, it never gave me an error message, as did TB, but the email never went through either. However, several hours later, I got a message from it saying that my sync settings were out of date. I never changed anything though. And then, it started working again. Thanks so much for your help. I was prepared to keep at this and was thinking about how to break through the Spectrum wall. But now it's working. Perhaps, my hours on the phone with their "script jockeys", eventually got passed up the food chain.

Today I spent about an hour on chat with Spectrum's level 1 and level 2 support about this issue. I also told them about another person who was able to find the fix on Spectrum's website, which was to change outgoing server port from 587 to 465, which didn't work for me. It ended up with them insisting it's Thunderbird's fault because I can send email thru Spectrum's webmail.

It ended up with them insisting it's Thunderbird's fault because I can send email thru Spectrum's webmail.

That is not apportioning blame, that is their service standard. You can send mail using web mail so they have met their advertised option to allow you to send mail.

Then they tell you to go away and look for help somewhere else as you are costing them money paying someone for nothing as you can use web mail.

I bet they never offered to look at their SMTP server log while you sent an email to find out why there is an issue.

Discussion here is about this error

impout006.msg.chrl.nc.charter.net cmsmtp 47.133.133.131 blocked. Please see https://www.spectrum.net/support/internet/understanding-email-error-codes for more information. AUP#Out-1130."

This is an error generated by Spectums server stating that the IP address 47.133.133.131 is blocked from sending mail. It has nothing to do with Thunderbird at all beyond Thunderbird reporting the error issued to it by the server.

It does however indicate the IP address https://dnschecker.org/ip-blacklist-checker.php?query=120.146.240.131 which is allocated to Charter communication and allocated to you is the reason.

This IP address is entered in a mail blocklist. https://dnschecker.org/ip-blacklist-checker.php?query=120.146.240.131 I have no idea if spectrum use this Brazilian list or not.

Fundamentally here is the problem. Spectum is refusing mail from their customer using the IP address they allocated submitted to their mail server for transmission telling you the problem is they are refusing mail from your IP address. The problem is at spectrum with their SPAM filters on their SMTP server, What are valid rules for port 25 (incoming mail to their network from other sites) do not necessarily apply to ports 465 and 587 (mail submission from customers). Unfortunately there is apparently no one at Spectrum competent enough to actually work that out it would appear based on your support experiences. They are simply refusing to accept mail and blaming others for their actions. I have one word that describes that, but polite rules make me not use it here. I can offer nothing more. Until Spectrum fix their system you will not be able to send mail using their servers with Thunderbird.

There is perhaps a way to spoof your IP address that might get it to work. No guarantees as this is really not particularly kosher. Use the config editor to set mail.smtpserver.default.hello_argument and enter the value spectrum.com so Thunderbird tells the server that the address is spectrum.com instead of the reported IP address. It might fool the server, or it might do nothing.

But I reinterate the problem is with spectrum and they need to fix it.