Hey Everyone, Please see the attached link to help you with this issue. http://www.vtdesignworks.com/blog/comcast-xfinity-port-25-blocked-change-to-465-or-587-for-outgoing-email-smtp Below is part of the information I found at this link. Hope it helps... *UPDATED 3-4-13 – Scroll for Simplified Instructions and Screenshots* Comcast Xfinity to Block Port 25 As part of a lengthy and technical blog post about internet security on August 1 of this year, Comcast Voices mentioned that they’d be phasing out support for Port 25 as an option for customers’ outgoing email server (SMTP). The post, which few people likely ever saw, didn’t exactly convey a sense of urgency, but did link to another post written the same day, explaining specifically why Comcast Xfinity would soon be blocking of Port 25 (emphasis mine): Over the past few years, Comcast has managed port 25 by selectively blocking its use in response to spam complaints. This made sense when spam was often sent by an end-user clicking a “send” button. But in this age of bot networks, malware is now responsible for sending the most spam and users are unaware that spam is being sent by their computer. As a result, we are updating our management of port 25. In order to ensure a more secure network and email domain, Comcast will no longer by default allow access to port 25 for our residential Internet users. In addition, we are asking comcast.net email users to migrate to port 465, which offers SSL encryption. We will continue to support the industry standard port 587. Upon request to our Customer Security Assurance team this block can be removed, enabling access to use port 25 for other email domains, though the comcast.net email servers will no longer accept submission via port 25. These changes will occur gradually across our network beginning today. Translation: Spambots take advantage of Port 25′s vulnerabilities and use it to send spam from user’s computers. For that reason, Comcast will soon block this outgoing email port for users that use an email client on their computers (rather than webmail), such as MS Outlook, Mozilla Thunderbird, etc. Many ISPs have blocked this port for some time, but it’s a new change for Comcast Xfinity users. It’s important note that this change has the potential to affect any Comcast Xfinity internet customers who use email software on their computer. While it’s probably a good idea to change your outgoing port settings to 465 or 587, as Comcast advised above, they do state that for non @comcast.net email accounts, they will unblock port 25 upon request. We would however just advise that you change your port settings to make things easier. *UPDATE – Many Comcast subscribers have found that 465 (Comcast’s recommended port) isn’t working, but 587 is* See link http://www.vtdesignworks.com/blog/comcast-xfinity-port-25-blocked-change-to-465-or-587-for-outgoing-email-smtp for more..
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I am having the same problems as everyone else. I am using Microsoft Outlook 2010 which I have been using for over a year - with 3 accounts. 2 accounts are Comcast email accounts; using incoming and outgoing comcast servers. 1 account is my business account which logs onto my pop domain server for incoming and smtp.comcast.net for outgoing. Everything - was working fine up to last week. Then all 3 accounts were unable to log onto my OUTGOING smtp.comcast.net server. Still able to receive messages but unable to send. So I logged into my comcast account via the web and found this link http://customer.comcast.com/help-and-support/internet/configure-outlook-2010-xfinity-email There I learned that there was a problem with Configuring Outlook 2010 for Xfinity Email. So I reconfigured according to this link and 2 of my email accounts are now working. Both of those accounts were Comcast accounts. The 1 account that is still not working is my POP3 business account which my incoming server points to my domain and my outgoing is still set to 25. Any ideas?
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