Solved: ISP (Cox) smtp port blocking

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hconant🇺🇸

ISP (Cox) smtp port blocking

I have relocated my SBS2003 exchange server from Verizon to Cox. Cox residential service appears to block port 25 out as well as inbound. To get around this I tried to setup dyndns mailhop to port 2525. I set up port 2525 on my WAN NIC at the virtual server. However I still am unable to telnet externally to port 2525 or port 25. I can internally so I know the box is set up ok. I can telnet externally to port 443 so I know the firewall and other settings are OK. Would Cox really block other ports, like 2525? I don't want to waste to much time on this if they do. I am trying to move my exchange box seasonally to different geographic locations, thus changing ISPs, even though it sould a bit weird. I could just get the Cox business service, but it requires a 1 yr contract and since my office is set up 6/6 months at different locatoins that is a stretch. Thanks for any ideas. My external IP is 68.225.209.148 if you want to try it yourself.

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ryansoto🇺🇸

Cox is known for doing this, I believe they also block 2525 after talking to a technician that came on site one day.
I also tried to install an exchange box behind their service and no go without the business class line.

kieran_b🇦🇺

You will find that you are in breach of their T&C by running a server on a residential line.

I don't think it is appropriate for us to help you with this issue.

Sorry

Kieran

hconant🇺🇸

ASKER

Actually, I have read Cox's T&C's and do not think using MS Exchange as a platform for home, non-commercial use is a technical breach of their "server" clause since I do not use exchange as a "server like functionality in connection with the Service." (quote from cox) I simply use it to retrieve my email from other isps that I also have accounts with and do not "serve" any of the mail to anyone else, exchange makes my backups easier, and it certainly is not used commercially. As such, I do not feel morally flawed by simply attempting to get my email into my chosen software platform. I would gladly use their business service if it were not for the 1yr contract, and rather steep setup charge. I would certainly be easier than spending days trying to come up with a workaround.

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kieran_b🇦🇺

>>I simply use it to retrieve my email from other isps that I also have accounts

That is a server. It is serving you.

This is a bit of a grey area - I am not trying to be unhelpful, but by the same time, I can't start dishing out information on how to bypass your ISPs security.

I have an idea to bypass this, but let me ask for the mods opinion on whether or not I can.

Until then I would urge other experts to not post.

kieran_b🇦🇺

Actually, I have a solution which should still fit in with their T&C

Use your ISPs mailserver as a smarthost

http://www.amset.info/exchange/smtp-connector.asp

Kieran

hconant🇺🇸

ASKER

I can appreciate your sensitivity to licensing compliance. It affects my line of work also, so I share your consideration. However, I view this particular issue as one of the intent, or, as commercial vs non-commercial, which is what I believe is the intent of Cox's server clause. If it were not, then just having multiple POP3 accounts that you retrieve with Outlook could be considered a form of server. Reading Cox's info, it seems clear they implemented the port blocking as an anti spam and security measure, not as a means of blocking SMTP mail because of commercial useage. So, I hope that helps it sit easier with you and the moderators. I'll take a look at the link you provided. THANKS.

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kieran_b🇦🇺

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