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BBStores
Premium
join:2005-10-02
Stone Mountain, GA
Reviews:
·Comcast

[Services] ATT U-Verse E-mail

My customer uses the Outlook 2007 client on a laptop with an ATT U-verse named xxx@bellsouth.net email account at her home. Used to work, now it does not with all online and ATT support setting changes. WHAT is the problem when this same email account and same laptop can send and receive email when I use it on my Comcast network at my home?



NetFixer
Freedom is NOT Free
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage

The most likely cause would be DNS. It could also be a problem with a security setting or security application on the notebook. You would need to supply some specific information in order to get a more specific diagnosis.
--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.



BBStores
Premium
join:2005-10-02
Stone Mountain, GA

Thanks. I will try to use my DNS settings (OpenDNS) on her network. Is it helpful to know that I can successfully ping both ATT servers inbound.att.net and outbound.att.net from each different location?



NetFixer
Freedom is NOT Free
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage

2 edits

said by BBStores:

Thanks. I will try to use my DNS settings (OpenDNS) on her network. Is it helpful to know that I can successfully ping both ATT servers inbound.att.net and outbound.att.net from each different location?

If you can ping them by hostname then DNS is probably working.

Try doing an nslookup from both locations if you want to see for sure that DNS is working. Also, be aware that different DNS servers can return different results due to geographic load balancing. For example, shown below are the nslookup results using OpenDNS, AT&T, and Comcast DNS servers; notice the differences.


C:\>nslookup inbound.att.net. 208.67.222.222
Server:  resolver1.opendns.com
Address:  208.67.222.222
 
Non-authoritative answer:
Name:    pop-att-new.mail.am0.yahoodns.net
Address:  98.139.213.175
Aliases:  inbound.att.net, pop-att.mail.yahoo.com
 
C:\>nslookup outbound.att.net. 208.67.222.222
Server:  resolver1.opendns.com
Address:  208.67.222.222
 
Non-authoritative answer:
Name:    smtp.att.mail.fy4.b.yahoo.com
Addresses:  98.138.84.52, 68.142.198.51
Aliases:  outbound.att.net, smtp-att.mail.yahoo.com
 
C:\>nslookup inbound.att.net 68.94.156.1
Server:  dnsr1.sbcglobal.net
Address:  68.94.156.1
 
Non-authoritative answer:
Name:    pop-att-new.mail.am0.yahoodns.net
Addresses:  67.195.132.60, 98.138.197.212, 98.139.213.175
Aliases:  inbound.att.net, pop-att.mail.yahoo.com
 
C:\>nslookup outbound.att.net 68.94.156.1
Server:  dnsr1.sbcglobal.net
Address:  68.94.156.1
 
Non-authoritative answer:
Name:    smtp.att.mail.fy4.b.yahoo.com
Address:  68.142.198.51
Aliases:  outbound.att.net, smtp-att.mail.yahoo.com
 
C:\>nslookup inbound.att.net 75.75.75.75
Server:  cdns01.comcast.net
Address:  75.75.75.75
 
Non-authoritative answer:
Name:    pop-att-new.mail.am0.yahoodns.net
Address:  98.139.213.175
Aliases:  inbound.att.net, pop-att.mail.yahoo.com
 
C:\>nslookup outbound.att.net 75.75.75.75
Server:  cdns01.comcast.net
Address:  75.75.75.75
 
Non-authoritative answer:
Name:    smtp.att.mail.fy4.b.yahoo.com
Addresses:  68.142.198.51, 98.138.84.52
Aliases:  outbound.att.net, smtp-att.mail.yahoo.com
 



--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.


BBStores
Premium
join:2005-10-02
Stone Mountain, GA
Reviews:
·Comcast

NETFIXER: Thanks for all your input. DNS seems to be working properly. I remoted into the laptop in question, added OpenDNS server names to the properties of the wired and wireless connections and the client Outlook errors did not change. Further research on this problem finds a solution posted 11/2012 that says: Log into this WEB based customer account at yahoo.com with the same Outlook email/pwsd parameters. Did that, and now the password request from the Outlook account goes away on SEND / RECEIVE, and I was able to send to the account, but the account labors to send out an email. Is this telling me ATT has an ACL problem? How could I find out what the ATT ACL setting are?



NetFixer
Freedom is NOT Free
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage

said by BBStores:

NETFIXER: Thanks for all your input. DNS seems to be working properly. I remoted into the laptop in question, added OpenDNS server names to the properties of the wired and wireless connections and the client Outlook errors did not change. Further research on this problem finds a solution posted 11/2012 that says: Log into this WEB based customer account at yahoo.com with the same Outlook email/pwsd parameters. Did that, and now the password request from the Outlook account goes away on SEND / RECEIVE, and I was able to send to the account, but the account labors to send out an email. Is this telling me ATT has an ACL problem? How could I find out what the ATT ACL setting are?

Ever since AT&T started using Yahoo! for their email service, there have been problems where individual email accounts had problems accessing and/or sending email in general or only from specific connections. Part of the problem is synchronization of the authentication between AT&T and Yahoo!, and can be DNS related wherein the client is connected to a different set of servers depending on which IP addresses are returned at any given time by a DNS query (which can change depending on the DNS servers being used, the physical location of the client, and the IP address being used by the client's PC.

What I have found to work for my notebook (since it is subject to using multiple DNS servers and getting different IP addresses depending on from where and how it connects) is to use only AT&T email servers (with Yahoo! being taken out of the equation). I have never had the random access problems if I use the POP3 and SMTP servers listed below (but as always, YMMV):

POP3: fpostoffice.isp.att.net, SSL, port 995
SMTP: fmailhost.isp.att.net, SSL, port 465

The nslookups for those servers partially shows why:


C:\>nslookup fmailhost.isp.att.net. 208.67.222.222
Server:  resolver1.opendns.com
Address:  208.67.222.222
 
Non-authoritative answer:
Name:    fmailhost.isp.att.net
Address:  204.127.217.18
 
C:\>nslookup fpostiffice.isp.att.net. 208.67.222.222
Server:  resolver1.opendns.com
Address:  208.67.222.222
 
Non-authoritative answer:
Name:    fpostiffice.isp.att.net
Address:  67.215.65.132
 
C:\>nslookup fmailhost.isp.att.net. 68.94.156.1
Server:  dnsr1.sbcglobal.net
Address:  68.94.156.1
 
Non-authoritative answer:
Name:    fmailhost.isp.att.net
Address:  204.127.217.18
 
C:\>nslookup fpostoffice.isp.att.net. 68.94.156.1
Server:  dnsr1.sbcglobal.net
Address:  68.94.156.1
 
Non-authoritative answer:
Name:    fpostoffice.isp.att.net
Address:  207.115.11.18
 
C:\>nslookup fmailhost.isp.att.net. 75.75.75.75
Server:  cdns01.comcast.net
Address:  75.75.75.75
 
Non-authoritative answer:
Name:    fmailhost.isp.att.net
Address:  204.127.217.18
 
C:\>nslookup fpostoffice.isp.att.net. 75.75.75.75
Server:  cdns01.comcast.net
Address:  75.75.75.75
 
Non-authoritative answer:
Name:    fpostoffice.isp.att.net
Address:  207.115.11.18
 



While OpenDNS does return a different IP address for the SMTP server than do AT&T and Comcast DNS servers, there is only a single IP address returned instead of round robin load balanced IP addresses as occurs with the outbound.att.net server. Some email clients have problems using SMTP servers that use round robin load balancing (especially if the client is configured to use SSL). Also, the two AT&T servers I have suggested are not CNAME values for Yahoo! email servers (as are the inbound.att.net and outbound.att.net servers), so the authentication synchronization between AT&T and Yahoo! is less likely to be a factor.

As for your question about how can you find out if you are on some AT&T or Yahoo! ACL banned IP address, there really is no way to find out because neither AT&T or Yahoo! is going to discuss their security with an outsider.

--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.


BBStores
Premium
join:2005-10-02
Stone Mountain, GA

Netfixer: As of 9:00 PM EDT, this customer can RECEIVE email but I can't SEND any from her Outlook client via my remote access. Any other thoughts for tomorrow? Your suggestions have been very helpful and THANKS again!



NetFixer
Freedom is NOT Free
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage

3 edits

said by BBStores:

Netfixer: As of 9:00 PM EDT, this customer can RECEIVE email but I can't SEND any from her Outlook client via my remote access. Any other thoughts for tomorrow? Your suggestions have been very helpful and THANKS again!

If changing the email client to use:

POP3: fpostoffice.isp.att.net, SSL, port 995
SMTP: fmailhost.isp.att.net, SSL, port 465

did not fix it, then I can't think of much else to suggest. I have run into some email clients (and Outlook was one of them), that did not automatically change the port used for SMTP when you select SSL. If your Comcast connection does not block outbound port 25 connections (mine does not), but the client's AT&T connection does (AT&T blocks outbound port 25 for residential accounts, and even some small business accounts), that might be a possibility (if Outlook is accidentally configured to use port 25 for outbound SMTP).




--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.