Head Guru Posted February 19, 2005 Posted February 19, 2005 We have ran into a couple clients that starting having issues sending e-mail. After investigation it has turned out that a major ISP has started blocking outbound e-mail ports. Story is here... http://support.sbcglobal.net/article.php?item=4640 Quoted from the SBC Website - Port 25 filters For All Applications, All Operating Systems, and All Domains SBC Internet Services (SBCIS) is taking positive steps to help combat junk email and spam. In addition to network upgrades, free spam filtering and anti-virus software, SBC is implementing outbound SMTP port controls to ensure the SBC network is as reliable as possible for our Members. SBCIS began filtering Port 25 to separate outbound SMTP mail from dynamic IP mail. Most SBCIS Members already use SBCIS or Yahoo! SMTP mail servers for outbound email and will not be impacted by this filter. Members not using Web mail access or SBC mail servers, such as a private company or university mail server, will not be able to send outbound email until one of the following actions are taken: Convert your outgoing mail to the SBC mail servers. Contact your server administrator for information about alternate access methods allowing connectivity to the 3rd party mail server (i.e., VPN, Web mail or Outlook Web Access). Request that SBC removes the SMTP port filter from your account: on our Abuse of Service form, enter the details of your request in the Abuse Description field. Additional Resources & Updates These additional resources may be used if there is a possible issue with the SMTP port controls upgrade. Quote
TCH-Bruce Posted February 19, 2005 Posted February 19, 2005 Thanks for the info Bill. I have SBC DSL at work. Quote
Madmanmcp Posted February 19, 2005 Posted February 19, 2005 Bill, that link you supplied may not work correctly at first. It leaves you at a menu system which you need to select a connection type and a domain to reach the page. Any selection will get you there. SBC has been blocking port 25 for several months now, we've been answering complaints with email on our boards for some time now . They did a slow rollout on all the domains and I believe they have finally done them all (not positive on this). Its a pain for some folks but was a necessary decision. I rarely use my Prodigy dialup anymore and use my Cable company connection for outgoing and have authentication set and use port 25 with no problems. But this is the reverse of what you are talking about . Others want to use the SBC connection to send outgoing mail for their other email accounts and its now being blocked. This will become the "norm" for everyone so the complaints will continue as more and more ISP's convert over to blocking. Quote
TCH-Dick Posted February 19, 2005 Posted February 19, 2005 Here is a list of other ISPs that block port 25, I'm sure there are many more this list is the result of a 60 second google search. AT&T MindSpring BellSouth MSN CableOne NetZero Charter People PC Comcast ATTBI Sprynet Cox Sympatico.ca EarthLink Verio Flashnet Verizo MediaOne Quote
Deverill Posted February 20, 2005 Posted February 20, 2005 Sorry to be thick, guys, but I have 2 questions. 1. Is this new SBC thing as simple as a port 25 block? 2. How can port 25 blocking help? It seems almost everyone uses 26 as an alternate so won't the spammers just go 25-26-27? Quote
TCH-Bruce Posted February 20, 2005 Posted February 20, 2005 Jim, here's my thinking. If you use port 26 you still have to authenticate. At least here at TCH anyway. You still have to connect to some mail transport system to send. Quote
Madmanmcp Posted February 20, 2005 Posted February 20, 2005 Jim, 1. I don't think its a "simple" port 25 block. Its more complicated in that its blocking access to port 25 for any IP that is outside of SBC's IP ranges. And with all the ISP's that SBC has gobbled up the "include" list of SBC's IP's is very large and spread all over the place. 2. Yes the spammers can switch to 26, but having to authenticate is difficult. From what I understand they currently write their own mail program. To get authenticated they would need to use the mail program on the machine they have taken over. Not impossible, just more difficult and more likely to be discovered. Quote
Head Guru Posted February 20, 2005 Author Posted February 20, 2005 Bob, It may have been in effect for several months, however it was only effect in selected service regions for deployment testing reasons. In fact it still has not been fully deployed. I have a business class DSL connection in my home, and never had a problem until last night, when with no reason my outbound email stopped working. After some research it was determined that SBC started blocking port 25. Bob you state "Its a pain for some folks but was a necessary decision" Whilst I respect your view, I do not agree. In my view it is the JOB of an ISP to give access to the internet and all that is internet, not block certain areas. While sure they allow outbound mail thru their own servers, many people do not want to use the ISP's servers. However, with the spread of windows based Virus's this is becoming more and more popular. The number of people still running infected machines, without up to date anti-virus programs is amazing to me. Just my 2 cents. Bill Quote
ToddPaxman Posted March 6, 2005 Posted March 6, 2005 Thank you, thank you, thank you, for answering this mystery for me! Since I coincidentally switched email clients at the same time, I of course thought it was me! -Todd Quote
Madmanmcp Posted March 6, 2005 Posted March 6, 2005 Bob you state "Its a pain for some folks but was a necessary decision" Whilst I respect your view, I do not agree. Sorry I missed your reply somehow. shhh, I agree with you but was just giving the party line here. Quote
Head Guru Posted March 6, 2005 Author Posted March 6, 2005 I have SBC DSL and they have as of last night unblocked my port25. There is a form that you can fill out and send to SBC to request that they unblock your port25. I did, and they did. Bill Quote
rbb213 Posted March 30, 2005 Posted March 30, 2005 I just put a check mark in the outgoing server requires a ssl conection, and it works for me... Quote
rbb213 Posted March 30, 2005 Posted March 30, 2005 wow...I just realized what I wrote...Although partially it is true...On some email servers, you can get away with that....but I am finding out as I mess with this,.....My other email only when sending its blocked.... That is using Lawton, Cablevision... Quote
rbb213 Posted March 30, 2005 Posted March 30, 2005 I found another cure.... Just use them as the Outgoing Mail Server... Just set your email for your Incoming Mail Server, and them put SBC on the outgoing.... all we'll end up doing is using up all their bandwith for sending mail..... Quote
Pendragon Posted March 30, 2005 Posted March 30, 2005 Bob,been fully deployed. I have a business class DSL connection in my home, and never had a problem until last night, when with no reason my outbound email Bob you state "Its a pain for some folks but was a necessary decision" Whilst I respect your view, I do not agree. In my view it is the JOB of an ISP to give access to the internet and all that is internet, not block certain areas. While sure Bill <{POST_SNAPBACK}> I have Cox (business), the residential accounts block pretty much every 'common' web port known, the business accounts block NO ports. This means residential accounts cannot act as servers, ftp, web, mail, nothing. Business accounts can, though with limited outgoing bandwidth it's still not good for much, and your DNS still shows as cox's, rather than whatever domain(s) you may be running. It's been like this for years with Cox. Quote
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