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Port 25 is blocked inbound and outbound

Discussion in 'E-mail Discussion' started by OgreMHDW, Jul 4, 2017.

  1. OgreMHDW

    OgreMHDW Member

    Feb 2, 2015
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    Henderson, Nevada, United Stat
    cPanel Access Level:
    Root Administrator
    I am trying to find out what I could have done to "block" port 25.

    When attempting to telnet from outside the system, I get:
    Microsoft Telnet> open server 25
    Connecting To server...Could not open connection to the host, on port 25: Connect failed

    I am able to telnet on the server, to itself:
    root@server [/etc]# telnet server 25
    Trying x.x.x.x...
    Connected to server.
    Escape character is '^]'.
    220-server ESMTP Exim 4.89 #1 Tue, 04 Jul 2017 07:57:24 -0700
    220-We do not authorize the use of this system to transport unsolicited,
    220 and/or bulk e-mail.
    I can then perform normal mail commands.

    When attempting to telnet from inside to Google:
    root@server [/etc]# telnet 25
    telnet: connect to address Connection refused
    Trying 2607:f8b0:4007:806::200e...
    telnet: connect to address 2607:f8b0:4007:806::200e: Network is unreachable

    Does anyone have any ideas? I am at a loss of where to go from here.
  2. cPanelMichael

    cPanelMichael Technical Support Community Manager Staff Member

    Apr 11, 2011
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    cPanel Access Level:
    Root Administrator

    It's not uncommon for service providers to block access to port 25 as a SPAM prevention technique. I recommend contacting them to see if that's the case.

    Thank you.
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