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421 Error when sending email IP address is not permitted to send messages

Regular Visitor

Re: 421 Error when sending email IP address is not permitted to send messages

I am having this same problem (again).

I suspect you are rejecting my VPN.

I don't see an option for PM on your profile.

 

 

An error occurred while sending mail:
The mail server sent an incorrect greeting:
 resomta-po-05v.sys.comcast.net
 resomta-po-05v.sys.comcast.net
 CSI IP 107.181.176.102 is not permitted to send messages.  
Please contact support if you feel this is in error..

 

(google) Search Results:
107.181.176.102
Your public IP address

Official Employee

Re: 421 Error when sending email IP address is not permitted to send messages

Typically this error happens when the IP has been sending a fair bit of spam.  I'm looking into the cause, but I'd expect that to be the reason.  I'll get back to you shortly.


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New Poster

Re: 421 Error when sending email IP address is not permitted to send messages

Thanks to whoever first mentioned VPN.  I shut mine down (temporarily) and was able to send.

New Poster

Re: 421 Error when sending email IP address is not permitted to send messages

Hello I am having the same problem. When sending emails in an email program I get the following message "An error occurred while sending mail: The mail server sent an incorrect greeting: resomta-po-11v.sys.comcast.net resomta-po-11v.sys.comcast.net CSI IP 217.156.208.210 is not permitted to send messages. Please contact support if you feel this is in error..". When I send emails from a browers they go through successfully.

Official Employee

Re: 421 Error when sending email IP address is not permitted to send messages

mrfluffy, thanks for posting about your email issues via the third party program. I recommend you reach out to our customer security assurance team to resolve this issue. They are working with folks on this thread but you can also call them here 1-888-565-4329. 


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New Poster

Re: 421 Error when sending email IP address is not permitted to send messages

If you have a VPN turn it off and reboot.  I was having the same problem (could recieve emails but not send them).  This worked for me.

Frequent Visitor

Re: 421 Error when sending email IP address is not permitted to send messages

Pretty much as an update, I still have this problem but it has not happened as frequently in the past 6 months.  As a restatement of my problem - with my VPN engaged, outgoing emails are blocked some of the time.  With the VPN turned off, no outgoing emails are blocked, ever.  When I first posted here about a year ago, about 80% of my outgoing emails were blocked.  Note that this was an intermittent problem and that some outgoing emails were sent over the VPN without any issue.  Currently, only about 5% are blocked.  My point is that the problem has not gone away entirely.

 

My guess is that, when you reboot, you are getting a new VPN connection that just happens to be using an IP that is not blocked by the service providers. 

Official Employee

Re: 421 Error when sending email IP address is not permitted to send messages

Hello all, 

 

@lortoad and @aluminum - Thank you so much for sharing the troubleshooting steps and your findings!


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Regular Visitor

Re: 421 Error when sending email IP address is not permitted to send messages

No prob. I always suspect VPN. You have to turn it off for Papa John's 🍕 too.
Official Employee

Re: 421 Error when sending email IP address is not permitted to send messages

A@ARLibertarian - No pizza with VPN? That's a bad deal


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New Poster

Re: 421 Error when sending email IP address is not permitted to send messages

I'm a computer technician with a customer that has an email account from comcast that he's using on a spectrum IP address that is being blocked.  The block goes away every 4-8 hours then it's right back.  Is there any way we can make this permanent? 

 

@ComcastAntiSpam 

Official Employee

Re: 421 Error when sending email IP address is not permitted to send messages

Sending you a PM


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Regular Visitor

Re: 421 Error when sending email IP address is not permitted to send messages

Having trouble sending outgoing emails from my Comcast email address on Outlook while on my home WiFi.  Have not problem sending them when NOT on WiFI or when sending while logged into the xFinity website.  Please help.

Official Employee

Re: 421 Error when sending email IP address is not permitted to send messages

I'll answer your PM shortly. @Finsta 


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New Poster

Re: 421 Error when sending email IP address is not permitted to send messages

Hello, I am having this same issue. This is the error message I receive:

 

421 resomta-po-02v.sys.comcast.net resomta-po-02v.sys.comcast.net Excessive failed authentication, ESMTP server temporarily not available

Official Employee

Re: 421 Error when sending email IP address is not permitted to send messages

@skip20101 Sending you a PM with some details to hopefully help resolve this.


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