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SMTP outbound blocked


SMTP outbound blocked

Got U-Verse + Internet.  Specifically asked if it was ok to run my own e-mail server (sendmail: personal use, personal domain, no hosted, no relay).  Was assured it was fine to do so, and that AT&T would setup my DNS PTR record for my static IPs.


Had to call in to remove the block on outbound SMTP (tcp 25).  They removed it, no problems for months.


Recently lost connectivity all day, think nov 2nd.  Outbound SMTP has been blocked again since.  Obviously an AT&T network problem.  "telnet <remote MX> 25" times out.  tcptraceroute dies at the AT&T 2wire router.  Remote mailservers never see any traffic from me when doing a packet capture on them.  My own equipment has been testing without any firewall at all beyond the at&t provided 2wire modem/router.


Uverse tech support level 2 tells me that outbound SMTP is not blocked, and that I should call Connect Tech.

Connect Tech tells me that it's an obvious network problem and I should call DSL tech support.

They refer me back to connect tech, who refers me back to tech support.  Over and over... all darn day.


What can I do?  I can't get anyone to escalate this issue to anyone that even knows what "SMTP" is.  I've had people try to walk me through setting up 'the outlook' (*sigh*... I don't even use windows let alone 'the outlook').  I had one tech insist that I *HAD* to use Yahoo webmail and that makes port 25 work.  (Really?)


So frustrated.


I know my stuff, I'm a high-end Linux and Network guy by trade.

I know AT&T is still blocking SMTP out.  I can't seem to convince anyone of this and just get the constant ping-pong between dsl tech and connectech.


There's just GOT to be some way to get this escalated beyond all these low-end call center reps.  Suggestions?  Anyone have a magic phrase that gets you past the connect-tech <--> dsl support loop?


Message 1 of 67

Re: SMTP outbound blocked becas

Great you're up and running again.


I don't understand what's up the port blocking lately either.

Message 46 of 67

Re: SMTP outbound blocked becas

At the risk of beating a dead horse, I now have an experience to share ...


I recently signed up for U-Verse DSL with the 8 static IP package in the Santa Clara, CA area.

Install went well, figured out how to config the statics on RG so far, etc.


However as many others have experienced, outbound SMTP on port 25 is blocked.


After reading many (many!) other peoples' experiences here and elsewhere, and because I'd

had a good experience with them for another issue, I decided to try emailing

to unblock port 25 for my address range.


FYI, the folks responding to my emails to that address have email signatures which say:


AT&T U-Verse Tier II Technical Support

Social Media Support Team


So I had hope I was reaching knowledgeable people who could actually help me -- the forums

almost always say "talk to Tier II to get help".


But cutting to the chase:  the technician tells me:


   "The port 25 filter is set to protect our network from spammers. Since
     your account is labeled as a Consumer account there is a onetime fee to
     unblock the port 25 filter. I can unblock the port if you will allow the
     charge of $29 to be added to your account."


So it sounds like I've found someone who can/will fix the situation, but there's the infamous

$29 fee again that I've read so much about.


Any advice on how to handle this before I agree to the $29 fee (ransom?) to restore acces

to port 25 ?  I never had to do anything like this in 10+ years as a regular DSL customer,

and never had blocked access to any common network services ports.

Message 47 of 67

Re: SMTP outbound blocked becas

Matt, who used to be on the Social Media Support team has stated over on DSL Reports that the $29 has been officially instituted and can't be waived, unfortunately.


My guess would be that AT&T wants only people who seriously have the need to have port 25 unblocked to have it done.  Many power users used to call and request the port be unblocked "just because" when they didn't really need or make use of that functionality.


You might, however, pay the $29 fee to have it unblocked, and then call billing and see if they can give you a small promotion on the TV service to make up for it.


Message 48 of 67

Re: SMTP outbound blocked becas

Thanks SomeJoe7777 -- interesting news about the $29.  I (politely) asked the Tier-II Social Media Support

Team technician for a pointer/URL/etc. which documents the fee policy.


I can understand AT&T's stance on not wanting spam to originate from their networks, and I can even

understand (to a lesser degree) the fee to unblock port 25.  My issue at this point is the way AT&T/U-verse

handle (don't handle) disclosing their policy and the fee.


E.g. if it were clearly stated or documented up-front during the customer sign-up phase, it wouldn't come as

a surprise and perhaps wouldn't be as objectionable to some people.


Fortunately I wasn't taken completely by surprise at the block nor the fee, from reading other's experiences

here in the forums; but it still seems to me that AT&T/U-Verse are doing a disservice to their customers by

not being more forthcoming, and effectively forcing us to rely on rumor, guesses, tribal knowledge, etc.


Message 49 of 67

Re: SMTP outbound blocked becas

- I thought every ISP blocked outgoing port 25.  I first encountered this with ATT (then SBC) about 10 years ago on a regular old DSL line.  I formally had COMCAST at home and they blocked it as well.

- The company I use to host my email provides port 587 as an alternative for outgoing mail. gmail also supports 587. This works fine for client to server connections on UVERSE and COMCAST. I've never had the need to run SMTP at home, so I don't know if server to server connections work on this port or not.

- even the guys explaining how to set up Outlook should have this information.

Message 50 of 67

Re: SMTP outbound blocked becas

Not all ISPs block outgoing port 25.  Many ISPs have customers who run their own mail/SMTP servers and therefore require

the ability to send messages to other mail servers and relays, on port 25.


In fact, I ran my own domain and mailservers on AT&T residential DSL (not U-Verse) for 10+ years and port 25 was never

blocked, nor was it ever even an issue as far as I know.  Of course, as has been mentioned elsewhere on this forum, "not

all AT&T's are created equal".  :-)  That is, what may be (have been) the case for PacBell could be different for SWBell etc.


The point about alternate ports is fine for some mail clients (Outlook, Thunderbird, etc), but as noted -- it doesn't apply if

you are running a mail server and need to deliver mail messages to/from other mail servers.

Message 51 of 67

Re: SMTP outbound blocked

Just wanted to add my 2cents - I just resently upgraded from DSL to U-verse and discovered my out bound email blocked.  At first I could not get anyone willing to help without me paying first.   Then I found this forum.  I called back and requested to have my port 25 unblocked.  The first guy wanted to send me to Connect Tech like the earlier messages said.  I requested Tier 2 support instead and got it.  The first guy again wanted to send me to Connect Tech and said there was a $29 charge to unblock port 25.  I refused and told him I was reading on this forum I would be sent to Connect Tech if the person I was talking to didn't really know what he was doing and I would rather call back and try again.  Which I did.  This time I told the first guy I was having email issues and I wanted my port 25 unblocked - to my surprise instead of wanting to send me to Connect Tech he said he could do that and asked if he could put me on hold a minute - I said yes - he did - he came back within a couple minutes and asked to try it again.  He did it - my email started working and I didn't have to pay the ransom.


I want to thank this forum -  I was ready to dump U-verse and go to cable.  Now I might keep it a while.

Message 52 of 67

Re: SMTP outbound blocked

Thanks for letting us know it CAN still be done without a charge, and a little persistence. Smiley Wink

Message 53 of 67

Re: SMTP outbound blocked

We had the same problem at work. We had to switch from att dsl to att uverse. After the switch outlook express wouldn't send email with the settings that had just worked on the previous dsl service. Went through all the settings to change  - port 465 register email addresses thru the yahoo/att account ...... bunch of crap. We just wanted to send email thru our server. Do we really have to go thru att\yahoo email? Turns out that a simple change in settings in outlook express from port 25 to 587 was all that  needed changed! Wish I had found this out before I spent 6 hours messing with settings and reading thru all kinds of posts! It was actually easy to find the answer in the att support page. I just typed "port 25" in the ask a question box. I'm not a networking expert, so maybe this is the wrong answer for you, but it did solve our out going email problems. I think att should have made this much easier to find - the tech could have even mentioned it, or at the very least the support people on the phone (if you can actually get through) should have the answer. Hope this helps someone. JIM



Message 54 of 67

Re: SMTP outbound blocked

1st call: I ended up at Tier 1 and he logged into my RG and said that port 25 was already open. Started asking about my email client, etc. OK, thanks for your help.


2nd call: Started at Tier 1, said they could send me to ConnectTech. I asked for Tier 2. Tier 2 agent looked and couldn't find anything and said that ConnectTech could do it for the $29 fee that I could probably deactivate immediately and not get charged. No thanks, I'll keep trying.


3rd call: Tier 1 agent put me on hold for a couple of minutes, came back and said to try again. I confirmed that he wasn't just checking the RG and he said he was using another tool on my account to unblock port 25. It didn't work initially and he said he would try it again. Then it worked! No Tier 2 or ConnectTech or $29 fee!


This was on 8/16/2011. It does take a little persistence to get through to someone who knows what they are doing. I used this same phrase every time "I would like SMTP outbound on port 25 unblocked". Don't try to over-explain or say that you need it to send email from your home server, etc. Just stick with that phrase. If they are adept with the knowledge base tools on their end, they will figure it out.



Matt (aka mottsmith321 ... seriously, who blocks specific letter combinations from a username? I couldn't have 'att' in my username)


Message 55 of 67

Re: SMTP outbound blocked

That's good to hear! 


It used to always be free, but seems they are just referring people to ConnecTech for simple things these days. Smiley Sad


Message 56 of 67

Re: SMTP outbound blocked

I had this issue when I first setup outlook to use my business address for outgoing reply's. CS said they didn't work with outlook but I would have to pay for their contech support. At the time I had no idea what was happening and thought I would call my hosting company they had me change my outgoing port to 26. Works well no problem.


Try port 26

Message 57 of 67

Re: SMTP outbound blocked

I have set up a private domain. It is registered correctly and has the proper MX records. I have my own DNS and mail server (postfix on a linux box). All of my mail works correctly except for outgoing. Yes port 25 was blocked but I was using 465 with tls/ssl. I would correctly autenticate with the server but continue to get 553 errors.


I have used on-line chat, tier 1, tier 2. They finally got me into ct for $15/month. So today I call in to check and tier 1 says they can't service me and escalate. Tier2 says that I have to use CT. I use connecttech online chat an the tech can't find my account info. He refers me to sales. Sales sees that I have ct and puts a tech on. After convincing hime I was talking about a server he checks and they unblocked port 25, I changed my server to use it and get the same error. Connecttech escaltes to tier2. They get yahoo support involved. It turns out that yahoo requires the from address to be registered. I need to take each user from my domain and add them under my email id for verification.


You have got to be kidding me. This is not a solution. So why did I have to give up my existing isp when I got uverse? So that I could use yahoo?

Message 58 of 67

Re: SMTP outbound blocked

Update to my post on 8/16/11:

I had to get a new u-verse account back in October (long story). I had to call in for the new account to get port 25 unblocked. I was successful on my first call to Tier 1.


Just remember to use the phrase that pays: "I would like SMTP outbound on port 25 unblocked"

Message 59 of 67

Re: SMTP outbound blocked

Thanks for the report, and that you were not charged.


I wonder what has happened lately with so many now being asked to pay for the change?

Message 60 of 67
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