Welcome to Xfinity Help & Support Forums
Find solutions, share knowledge, and get answers from customers and experts

New to the Community? Start here.

5,858,469

members

1,197

online

29,720

topics

Top

Re: I've been having repeated problems with ESMTP server not available

Regular Visitor

Re: I've been having repeated problems with ESMTP server not available

r

I get the following error for the last two days.  This problem has happened intermittently in the past but always cleared up in an hour or so.  now it has been two days.  it only affects outgoing emails

 

An unknown error has occurred.

Subject 'Fw: 
Server Error: 421
Server Response: 421 resomta-po-16v.sys.comcast.net comcast ESMTP server temporarily not available, please contact support
Server: 'smtp.comcast.net'
Windows Live Mail Error ID: 0x800CCC67
Protocol: SMTP
Port: 465
Secure(SSL): Yes

Frequent Visitor

Re: I've been having repeated problems with ESMTP server not available

Been having the exact same problem, almost the same server.  I tried an online chat and phone call with Comcast - completely useless.  They said they are not responsible when a client server is not working.  I think the problem is on their end - I previously found a list of their SMTP servers and all the names started with resqmta, not resomta.  Sorry I couldn't be of more help.

Frequent Visitor

Re: I've been having repeated problems with ESMTP server not available

Just to add another indicator of why I think this is a comcast problem, I have my iphone setup to use the same email settings as my desktop. I had my iphone use the wifi connection on my comcast router box.  I tried to send a test message and it failed with an error.  I dropped the wifi connection and switched to my verizon data connect and the email went through no problems, This is most likely a router problem at xfinity where we get switched to the wrong set of ESMTP servers (resomta) instead of the correct ones (resqmta).

Official Employee

Re: I've been having repeated problems with ESMTP server not available


ajahearn wrote:

Just to add another indicator of why I think this is a comcast problem, I have my iphone setup to use the same email settings as my desktop. I had my iphone use the wifi connection on my comcast router box.  I tried to send a test message and it failed with an error.  I dropped the wifi connection and switched to my verizon data connect and the email went through no problems, This is most likely a router problem at xfinity where we get switched to the wrong set of ESMTP servers (resomta) instead of the correct ones (resqmta).


The resomta servers (behind smtp.comcast.net) are the correct set for users sending via smtp auth.  The resqmta servers handle the "last hop" for messages going to external domains.

 

Your user account has over 2000 failed authentication attempts over the past week.  Did you change your password recently, and maybe you have some device that's still trying to send using an incorrect/old password?

 

 





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Regular Visitor

Re: I've been having repeated problems with ESMTP server not available

I can download all my incoming messages with no problem.  I tried switching my account from a pop3 to an imap account and I get the same errors.

 

I wouldn't doubt that I have left my email open for a period of time and it periodically tries to connect and then it fails with the same error I posted.  Also sunday night (7-31) at 8:08 pm EDT   I was able to send three emails that were in my outbox.  I don't know why it was successful then after all the failed attempts.  I tried again this am (8-1) and it didn't work.

 

I never changed my password or any settings during this period of time where it worked and then didn't work.

 

 

 

Official Employee

Re: I've been having repeated problems with ESMTP server not available


bbraunsdorf wrote:

I can download all my incoming messages with no problem.  I tried switching my account from a pop3 to an imap account and I get the same errors.

 

I wouldn't doubt that I have left my email open for a period of time and it periodically tries to connect and then it fails with the same error I posted.  Also sunday night (7-31) at 8:08 pm EDT   I was able to send three emails that were in my outbox.  I don't know why it was successful then after all the failed attempts.  I tried again this am (8-1) and it didn't work.

 

I never changed my password or any settings during this period of time where it worked and then didn't work.

 

 


Maybe the config on your device got corrupted?  For example, on the iPhone, the retrieving and sending mail passwords are specified separately.

 

Hope this helps,


ComcastDaveL





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Frequent Visitor

Re: I've been having repeated problems with ESMTP server not available

I appreciate someone at Comcast has tried to diagnose what is going wrong here.  But at least in my case, I only have two devices configured for email, iphone and win7 desktop, so a corruption doesn't make sense - they would both have to be corrupted.  Furthermore, how does it explain that sometimes the mail goes thru from that same device - corruption cannot suddenly appear and then disappear could it?  And I also have not changed my password in months.

Official Employee

Re: I've been having repeated problems with ESMTP server not available


ajahearn wrote:

I appreciate someone at Comcast has tried to diagnose what is going wrong here.  But at least in my case, I only have two devices configured for email, iphone and win7 desktop, so a corruption doesn't make sense - they would both have to be corrupted.  Furthermore, how does it explain that sometimes the mail goes thru from that same device - corruption cannot suddenly appear and then disappear could it?  And I also have not changed my password in months.


 

I'll send you a private message.





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Contributor

Re: I've been having repeated problems with ESMTP server not available

I'm having the same issue.  We've reconfigured all mail cleints and changed passwords.  The problem persists as long as mail is sent from within the Comcast cloud.  There's got to be a routing or DNS issue related to the SMTP servers for authenticated clients.

Contributor

Re: I've been having repeated problems with ESMTP server not available

This problem persists.  It's got to be on the Comcast side. It appears to be a routing issue.  We can't connect to the SMTP servers.  Maybe they are not properly configured for the right port  (587)?  I can traert the SMTP server(s) but can't authenticate.....except every couple of days...at night actually, then outbound mail goes.  Next morning, I get the 421 error again (421 resomta-ch2-18v.sys.comcast.net comcast ESMTP server temporarily not available, please contact support)

Contributor

Re: I've been having repeated problems with ESMTP server not available

seems like the same problem I've been trying to get resolved.

 

my post:

http://forums.xfinity.com/t5/E-Mail-and-Xfinity-Connect-Help/MULTIPLE-421-resomta-ch2-15v-sys-comcas...

 

Official Employee

Re: I've been having repeated problems with ESMTP server not available

BuckerooBanzai (apologies, thought this was your thread, I see it is not)

 

You are having the same issue as Philly78.  You have a UID that is causing your IPv4 address to get flagged.  It's the UID ending with a "6" coming from what appears to be your home IP.  If you're still unsure of which UID, I'll send you a private message.





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Contributor

Re: I've been having repeated problems with ESMTP server not available

Hey thanks, Yes I know which device that is.  Forgot that one was configured to email, so I missed the password on that one, I guess.   I have fixed it.  Can you or another engineer "unflag" my IPv4.....or whatever will re-enable my SMTP send ability?

Official Employee

Re: I've been having repeated problems with ESMTP server not available

Give it a whirl now.





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Contributor

Re: I've been having repeated problems with ESMTP server not available

You my friend are my hero.  There is joy in Mudville.  Thanks!

Regular Visitor

Re: I've been having repeated problems with ESMTP server not available

problem continues to be intermittent

 

was ok for past few days

 

now back

 

An unknown error has occurred.

Subject 'landscape designer'
Server Error: 421
Server Response: 421 resomta-ch2-15v.sys.comcast.net comcast ESMTP server temporarily not available, please contact support
Server: 'smtp.comcast.net'
Windows Live Mail Error ID: 0x800CCC67
Protocol: SMTP
Port: 587
Secure(SSL): Yes

Contributor

Re: I've been having repeated problems with ESMTP server not available

This issue is aparently due to devices within your netwrork trying to authenticate to the SMTP server with improper credentials (eg - wrong password). The ISP sees the repeated invalid authentication attempts as a possible brute force attack and they flag the originatiing IP address (external IP address of your network) as bad. The offending IP address gets blocked for some period of time and then the ISP automatically unblocks it; was some time each night for me.  I think one of my NAS strorage devices was the source of invalid SMTP authentication attempts. Check all PCs on your network and any peripherals that can send email notifications. If one is having trouble authenticating, the entire network, by virtue of its external IP address gets blocked.

Official Employee

Re: I've been having repeated problems with ESMTP server not available

bbraunsdorf:  Are you still experiencing this issue?





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Regular Visitor

Re: I've been having repeated problems with ESMTP server not available

I took buckaroobanzai advice and checked all my devices of which I don't have many.  I also checked my secondary email accounts (established for my kids a long while ago)  One of them may have changed their passwords to access xfinity streaming away from home.  If my windows live program was checking my account as well as the 3 secondary accounts (one with a bad password) maybe that was it.  I never received an error message that the account couldn't access email.  I was able to send messages this am so I will wait and see.  It last occured on Saturday.

Frequent Visitor

Re: I've been having repeated problems with ESMTP server not available

DeskTop + Laptop.   Started yesterday.  Like everyone else can receive  not send.

If I go online I can send/receive from the comcast web page.

 

same messages as everyone else

 

resomta-po-10v.sys.comcast.net

resomta-ch2-05v.sys.comcast.net

..ch2-18v...

 

yada yada yada

same one doesn't come up twice.

 

Did a hard reset of the router. 

Turned off Iv6 in network settings.

 

Tried in Windows Live Mail.

Tried in Mozillar Thunderbird.

 

Used settings found on xfinity web pages.

 

This stinks.  Kinda of sad Comcast doesn't know and you have to tell them there is a problem.

But, this is the 1st real email issue I've ever had with Comcast and I've had them for years.

 

 

Official Employee

Re: I've been having repeated problems with ESMTP server not available

dejal, Same sort of issue as the others.  You have some device behind your router (IPv6 is not the issue), that is attempting to incorrectly authenticate.  Please check your devices and settings, if you can't find it, I'll see if I can get more information about what system it might be.  The logs are telling me it's coming from "[192.168.1.145]" on your network.





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Frequent Visitor

Re: I've been having repeated problems with ESMTP server not available

192.168.1.145 is my laptop wired into the router.  I've unplugged the cable from the laptop and will check in awhile.  I tried sending a test e-mail on the desktop immediately following the plug pulling and still get the error.  I'll wait a bit and try again later.

 

 

Official Employee

Re: I've been having repeated problems with ESMTP server not available

dejal, What I was trying to say is that the logs are showing that one of your systems in your house is misconfigured and attempting to login with invalid credentials.  You need to find that system and correct that situation.  If you need more help figuring out which system it is, let me know.





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Frequent Visitor

Re: I've been having repeated problems with ESMTP server not available

Would have thought with laptop out of the mix, that it be prove that was the case. 

 

So,

 

I've turned the laptop back on.

 

What settings should smtp.comcast.net be set to?

 

Port 587

Auth. Method: Normal Password.

Connection Security: STARTTLS

 

?

Frequent Visitor

Re: I've been having repeated problems with ESMTP server not available

Those setting seems to have worked.    Desktop and laptop as of this moment are working fine.

New Poster

Re: I've been having repeated problems with ESMTP server not available

Hello - I am having the same problem as well. One email account's password was changed recently so we updated all of his devices as recommended. After that the mobile devices were working again, they were not previously when on WiFi but were fine on cellular.   I did not change my password on my email account but my laptop continues to get the error, and now the mobile devices are no longer working when on WiFi. As a sidenote, we are secondary on the account and are not on the Comcast network since we live in an area where Comcast in not available.  Thanks for your assistance!

Official Employee

Re: I've been having repeated problems with ESMTP server not available

I'll send you a private message with some details that may help.  I don't want to expose usernames here.





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

New Poster

Re: I've been having repeated problems with ESMTP server not available

Thank you to the Comcast person who helped us solve this problem within an hour of my post!! Your service was courteous, more timely than I could have hoped for, and very specific to our problem.  THANK YOU!

New Poster

Re: I've been having repeated problems with ESMTP server not available

I am having the same problem with sending emails.  I have several computers on my home network, but I only use one desktop to get email.  This is the 2nd time that I have had this problem over the last couple of weeks.   I may have changed my account password a few months ago.  What are your thoughts?

New Poster

Re: I've been having repeated problems with ESMTP server not available

I am having the same problem with sending emails.  I have several computers on my home network, but I only use one desktop to get email.  This is the 2nd time that I have had this problem over the last couple of weeks.   I may have changed my account password a few months ago.  What are your thoughts?

 

thanks

Official Employee

Re: I've been having repeated problems with ESMTP server not available

alphagoat, I'll send you a private message with the culprit. 





Community Icon
I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: Product, Support, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am an Offical Comcast Employee.
Official Employees are from multiple teams within Comcast.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark a Best Answer!solution Icon
Community Icon
I am a Comcast Employee.
Please post so people with similar questions may benefit.
Was your question answered?
Mark a Best Answer!solution Icon

Xfinity Forum Archive
About the archive project

Xfinity Forum Archive...

This is an archived section of the community.

Content in this area has been identified as outdated or irrelevant.

This change was done in an effort to make the forum easier to use and to keep only the most helpful and recent content active.

Post your questions in the Xfinity Community

Discussion stats
  • 30 replies
  • 1595 views
  • 1 kudo
  • 8 in conversation