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SBC DSL Filtering Port 25

by MagellanGuy / February 10, 2005 9:47 PM PST

With no advance notice SBC began filter port 25 and denying access to all SMTP server addresses except

After nearly a day of trouble shooting, an SBC tech admitted that SBC started filtering port 25 to add their support to fighting spam. They didn't seem to care that their spam-fighting zeal shutdown my company's out-going e-mail for a day.

While they never apologized for blocking port 25 with no notice, they did resolve the issue while I was on the phone. I guess some SBC rocket-scientist figured there was no reason why any subscriber needed to access their own SMTP server. I am constantly amazed at how slowly large companies move until they seize on a really stupid idea.

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At another ISP...
by R. Proffitt Forum moderator / February 10, 2005 10:40 PM PST

They offer a BUSINESS DSL connection that doesn't block said ports.


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cutting off services for your own good! (not)
by rsp4all / February 17, 2005 12:52 PM PST
In reply to: At another ISP...

Oddly enough, there are a lot of non-business customers that use other mail services for sending/receiving. i know a ton of people right now that are screwed becuase of the hap-hazzard blocking of ports.

next step in spam prevention, limit all non-yahoo activity to 1kb per minute?

it's great to try to stop spam, but cutting off the ability to connect to aspects of the internet that the diverse customer base needs is not a very bright idea.

thanks mr brainiac that decided to do this. i wonder if i'm still able to download dilbert comic strips? heck, i bet there is a new one that has a manager talking about how to stop spam....

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the aha moment
by sri272005 / February 14, 2005 4:36 AM PST

cant tell you how relieved I'm to see this post. I've been fighting with the sbc setup for couple of week(end)s to get my corp email work. I uninstalled all SBC applications but still things don't work. Everything is so slooow. I suspect the uninstall left lot of entries in Windows registry that are coming in the way of my system going to the network directly. When I mentioned this to tech support, they advised me to reload OS!!

can you help me with this?
how can i get rid of all SBC Yahoo! 'features' in my desktop? uninstall didnt seem to work.

I am using a wireless router - the router picks up the signal very well and my laptop which is directly connected to router works super fast but when I hook up my desktop to my router, things fall apart.

how did you fix the smtp port problem?
thanks in anticipation!

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Arghhh - Switch To Comcast
by webmistress25 / February 16, 2005 2:30 AM PST

So funny I've been through hell and back with SBC on my home lines and I completely disconnected from them last week. So happy to have Comcast and also all of my phone services are running through Vonage - I'm saving $600 per year and many many many headaches and phone calls to support lines with automated messages! Best of luck to everyone dealing with this I know my phone will be ringing off the hook.

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SBC DSL Filtering Port 25
by lwkids / March 1, 2005 2:00 AM PST

Please share with us, Magellan! How did you fix the problem? It's found its way to us now!


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Opt out of port 25 block
by TheoGoldin / March 1, 2005 10:42 AM PST

You can opt out through

Just choose "**Opt Out Port 25" under abuse details and fill in all the other information. They'll send you a message indicating that the block has been removed within 24 hours. It seems bizarre to use a spam reporting form for this purpose, but that's where it is.

In the meantime, if you need to send mail, temporarily change your SMTP server to

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Bypass port 25 blocking issue
by pangtat / March 28, 2005 10:26 AM PST

I have used AcrossMail Service to bypass port 25 blocking issue for a long time, great. Their website is


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SBC DSL Filtering Port 25
by MagellanGuy / March 1, 2005 1:18 PM PST

I just called SBC technical support and told them their actions were unconscionable and they were adversely affecting my business.

Don't take "no" for an answer and ask to escalate the call until they agree to unblock the port. Also, don't accept that it will take 72 hours to remove the filter. They removed the one blocking my port while I was on the phone.

Don't be rude; just persistent. After all you have common-sense and logic on your side!

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Does work?
by upi / April 13, 2005 2:57 PM PDT

I do not have SBC DSL, and cannot verify this, but...

Presumably, if you have SBC DSL, you also have an e-mail account with them. Since SBC uses authentication extentions on their SMTP server, couldn't you use that server as the 'Outgoing server' for all your accounts? Just wondering...


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Does work?
by MagellanGuy / April 14, 2005 2:22 AM PDT

I can authenticate when I'm at the location with the SBC connection, but I have several offices and each uses a different ISP for Internet connectivity. I would get a relaying error if I tried to push e-mail across SBC's SMTP server from one of the other locations.

Having our own dedicated SMTP server gives me more flexibility and a lot more security.

Once SBC opened the port, I was fine. My issue was that they closed the port without any notice and their insensitive solution was, "just use our SMTP server." Obviously, for my situation, that just did not work.

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Does SBCGlobal. net work?
by Newtimer / July 4, 2005 10:19 AM PDT

I was trying to set up file sharing and during the process decided to start over and reinstall. I first had to uninstall. After all was said and done I lost email that was saved for 3 months. I am sick as those emails were irreplacable. Evidently the uninstall deleted all email files with the sbc program. I communicated with the Tech Support explaining my problem...they led me through some procedures that I had already done and then told me I would have to contact my computer manufacturer as they couldn't help me.


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