About aluminum

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.  ... View more

Are you using a VPN?  If so, which one? ... View more

That Comcast employee tried to assist me but found no problem with my account.  They booted it up to tier 2 support who said the same thing.     The IP address that is being blocked is the IP address of the VPN server which can change in order to move the apparent source of the HTML request.  There probably is a block of IP addresses that my VPN vendor (PIA) needs to supply to Comcast so they can be whitelisted.  However, that would allow the evil-doer spammers, who would be using the same servers, to run amok.  At least, that is my understanding at this point.  ... View more

Here is my current status: The problem still exists. That is, outgoing mail from my Thunderbird client is blocked when my VPN is on. I attempted to change my VPN service from Private Internet Access to NordVPN but experienced the exact same problem. I contacted NordVPN and their response was, "(them) Unfortunately it will not be possible to send emails if your provider is Comcast whilst using a mail client. (me) Why is that? (them) This provider is known not to allow send outgoing mail with VPN." (Exact quote from chat session) The Comcast employee mentioned in a couple of the emails in this thread was very responsive and suggested using another email client since they could see no problem on the Comcast side (even after I pointed out what NordVPN had said which mirrors what Private Internet Access says). I tried SeaMonkey and MailBird and outgoing mail was blocked with both as long as the VPN was active. They both worked fine when the VPN was turned off. I believe I have ruled out anything from the client side of this issue. If there are other suggestions, please don't be shy. ... View more

This seems to be similar to my problem but I am not sure as I don't fully understand what is happening.  Here is a link to understanding the 421 SMTP error but it basically says that this error is a general failure: https://www.inmotionhosting.com/support/email/bounceback-errors/email-error-421   I would post this as a public response to my posting to show that others are getting similar errors.  Also, send a private message to ComcastAmir (see previous emails in the public thread) as he was at least willing to check it out (whatever that means).  He found no problem with my account settings, forwarded it to the "second tier", who also found no problem.  End of story as far as Comcast is concerned.   Hope you can find a solution.  Keep me posted if you do. ... View more

I believe I have tracked part of my problem to my VPN provider - Private Internet Access.  They reported to me that they have started a whitelist of smtp providers.  What I don't understand (and I am waiting for a response from them) is that they want the IP address of smtp.comcast.net so that they can add it to their whitelist.  Unless I misunderstand, they can get this themselves with a ping.  With my VPN disconnected (not just 'exited'), I have no problem sending email to either of my SMTP services (comcast and aplus).  Can someone from Comcast talk with the PIA people?  It's not like Comcast and PIA are mom-and-pop corner stores.  This has got to be a problem for a lot more folks than just me.  PIA says that they have arrangements with other providers of email services to allow SMTP from their servers including AOL, Gmail, Outlook, and Yahoo.  They (PIA) want to block spammers and apparently those other email providers are actively doing something about spammers.  It is not clear to me why Comcast is not included in that group.     ... View more

On further testing, I believe that my version of this problem is affected by my VPN.  I use a VPN client that has a "disconnect" and a separate "exit" button.  I thought I was turning the VPN off when I "disconnected" (in this case, I would still get the error message when I tried to send an email).  When I "exit", I do not get the error message and can send email.  I am doing further testing by uninstalling the VPN on one computer and leaving it installed on another to see what I get.  It makes some sense to me that Comcast may be blocking the IP addresses of the VPN servers and, by disabling the VPN, I no longer run afoul of their blocker. ... View more

I'm using the Arris modem supplied by Comcast and the Surfboard SB6141 as my router. ... View more

I have been having the same problem for a couple of weeks now: An error occurred while sending mail: The mail server sent an incorrect greeting: resomta-ch2-09v.sys.comcast.net resomta-ch2-09v.sys.comcast.net CSI IP xxx.xxx.xxx.xxx is not permitted to send messages. Please contact support if you feel this is in error.. I have contacted Comcast a couple of times and they have escalated the problem a couple of times. A couple of days after the escalation, the problem is solved for some brief period of time and then it re-occurs. The IP address that is not permitted to send messages is different in each episode since I am using a VPN. The problem still exists with the VPN turned off, however. Rebooting the router, turning antivirus off, etc. does not resolve the problem. ... View more