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

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
said by BBStores:

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?

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.


Forosnai

join:2011-09-30
kudos:2
reply to BBStores
Learn: »www.247-host.com/support/index.p···cleid=15

Correct the client mail settings per your clients ISP:
»www.att.com/esupport/article.jsp···r_iViZJ1

Edit to add that the problem has nothing to do with dns and everything to do with the mail servers, ports, and authentication.


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

Learn: »www.247-host.com/support/index.p···cleid=15

Correct the client mail settings per your clients ISP:
»www.att.com/esupport/article.jsp···r_iViZJ1

Edit to add that the problem has nothing to do with dns and everything to do with the mail servers, ports, and authentication.

Regardless of what AT&T or Yahoo! POP3 and SMTP servers the OP's client is using in the email client, if it works properly from a Comcast connection, but doesn't work from an AT&T connection, the most likely cause is DNS (with the most likely secondary cause being an ACL in the servers that is blocking specific incoming IP addresses).
--
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
I've gone through a lot the past few days with your suggestions and others. Today, I have the laptop in question back on my Comcast network and it sends and receives with ease. What do you think Outlook is telling me when it works on a Comcast network and not on an ATT network?


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

I've gone through a lot the past few days with your suggestions and others. Today, I have the laptop in question back on my Comcast network and it sends and receives with ease. What do you think Outlook is telling me when it works on a Comcast network and not on an ATT network?

I posted my thought on that in your other thread on this same subject (the link is shown below). Did you try changing the POP3 and SMTP servers, and/or making sure that the SMTP server was not using port 25 as I suggested in your other thread on this subject?

I have seen problems caused by the use of round-robin DNS for SMTP (especially when SSL is used), and the SMTP server you mentioned using (outbound.att.net) uses round-robin DNS (depending on which DNS servers you use).

I have also seen problems caused by Outlook not automatically changing the SMTP port from 25 to 465 when using SSL (and that could be a problem for AT&T since they routinely block outbound port 25, but not for Comcast since their port 25 blocking is not universal).

There is also still the possibility of an ACL (or spam blacklist) block, or a routing problem based on your client's IP address, that might be bypassed if you change the SMTP server being used. And of course, your Comcast connection would have a different IP address which would bypass either an ACL block or routing problem.

»Re: [Services] ATT U-Verse E-mail
--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.


brookeKrige

join:2012-11-05
San Jose, CA
kudos:3
reply to BBStores
If laptop has a telnet client (from a terminal/DOS command line or otherwise, I use a UNIX shell below), use it to crudely verify connectivity to the various mail servers. This just provides another data point (network can connect or not) to narrow further investigation; doesn't immediately solve your problem.

For example, earlier ATT esupport article mentions outbound.att.net at port 465 (as mandatory: thus don't even test for port 25). My input in bold (control-] shown as ^]):

% telnet outbound.att.net 465
Trying 67.195.15.5...
Connected to smtp.att.mail.fy4.b.yahoo.com.
Escape character is '^]'.
^]
telnet> quit


That results says "Connected to ..." confirms my computer and network CAN connect to that server/port combination. Also at least in this one instance, DNS did not fail to resolve that server to a numeric IP address.


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

If laptop has a telnet client (from a terminal/DOS command line or otherwise, I use a UNIX shell below), use it to crudely verify connectivity to the various mail servers. This just provides another data point (network can connect or not) to narrow further investigation; doesn't immediately solve your problem.

For example, earlier ATT esupport article mentions outbound.att.net at port 465 (as mandatory: thus don't even test for port 25). My input in bold (control-] shown as ^]):

% telnet outbound.att.net 465
Trying 67.195.15.5...
Connected to smtp.att.mail.fy4.b.yahoo.com.
Escape character is '^]'.
^]
telnet> quit


That results says "Connected to ..." confirms my computer and network CAN connect to that server/port combination. Also at least in this one instance, DNS did not fail to resolve that server to a numeric IP address.

The "earlier" ATT esupport article is wrong:


webhost:/ # telnet outbound.att.net 25
Trying 98.138.84.52...
Connected to outbound.att.net.
Escape character is '^]'.
220 smtp112.sbc.mail.ne1.yahoo.com ESMTP
quit
221 Service Closing transmission
Connection closed by foreign host.
 
webhost:/ # telnet outbound.att.net 587
Trying 98.138.84.52...
Connected to outbound.att.net.
Escape character is '^]'.
220 smtp111.sbc.mail.ne1.yahoo.com ESMTP
quit
221 Service Closing transmission
Connection closed by foreign host.
 
webhost:/ # telnet outbound.att.net 465
Trying 98.138.84.52...
Connected to outbound.att.net.
Escape character is '^]'.
quit
^CConnection closed by foreign host.
 



Also the dig query below shows another potential problem with using outbound.att.net (especially when using SSL). Some email clients do not like SMTP servers that use round-robin DNS, and SSL especially does not like the way the round-robin DNS can sometimes cause the IP address to change in the middle of a session. In the case of using outbound.att.net, it is the possibility that the IP address can dynamically change that is potentially a problem, not that a DNS query doesn't return an IP address.


webhost:/ # dig outbound.att.net
 
; <<>> DiG 9.7.6-P4 <<>> outbound.att.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 24648
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 0
 
;; QUESTION SECTION:
;outbound.att.net.              IN      A
 
;; ANSWER SECTION:
outbound.att.net.       401     IN      CNAME   smtp-att.mail.yahoo.com.
smtp-att.mail.yahoo.com. 1071   IN      CNAME   smtp.att.mail.fy4.b.yahoo.com.
smtp.att.mail.fy4.b.yahoo.com. 210 IN   A       68.142.198.51
smtp.att.mail.fy4.b.yahoo.com. 210 IN   A       98.138.84.52
 
;; Query time: 0 msec
;; SERVER: 192.168.9.2#53(192.168.9.2)
;; WHEN: Mon Dec 31 20:23:50 2012
;; MSG SIZE  rcvd: 137
 



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


Forosnai

join:2011-09-30
kudos:2
reply to BBStores
said by BBStores:

What do you think Outlook is telling me when it works on a Comcast network and not on an ATT network?

That you need to start from scratch from behind the clients' Uverse connection to reveal any number of things that can prevent the mail from syncing: software firewall, 3rd party network devices, even physical problems with the customers Uverse install, ad infinitum... could be the real culprit.
Webmail and IMAP solutions really save the day for problems like this.


BBStores
Premium
join:2005-10-02
Stone Mountain, GA
Reviews:
·Comcast
The problem here was the Outlook 2007 app...laptop back in my shop over the holiday weekend...uninstalled MS Office 2007...re-installed MS Office 2007...send and receive with Outlook on my office Comcast network...returned laptop to customer and was able to send and receive on her ATT network...solution was an uninstall and re-install of MS Office 2007...THANKS for all input.


shortyd999

join:2008-10-21
Birmingham, AL
The simplest solution is usually the best solution.