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bridgemoreuserman's profile

7 Messages

Tuesday, February 20th, 2024 4:18 PM

Home Internet - HP Laptop user - I need TCP or UDP info to open ports 25 and 53 on my firewall. HELP?

I just bought a new HP laptop and I need to open ports 25 and 53 on my firewall.  I don't know the protocol type (TCP or UDP).  Any ideas on this needed information?

ACE - Expert

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35.5K Messages

3 months ago

SMTP is TCP port 25.

DNS is UDP port 53.

AT&T blocks TCP port 25 traffic originating from a consumer account.  That's a very hard thing to get removed.  I have no guidance on how you would get it unblocked.  However, you can typically use another port to communicate with most SMTP servers.

I have no information on AT&T blocking UDP port 53.  This should not be an issue for you.

https://about.att.com/sites/broadband/network provides additional information on AT&T network practices.

3 months ago

My AT&T tech support is asking for a 4 digit code for each one (TCP & UDP).  Do you know what the 4 digit code for each?

ACE - Expert

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35.5K Messages

3 months ago

If AT&T Tech support is asking for a 4 digit code, it's most likely they want your account PIN.  

3 months ago

I know what you are referencing.  Unfortunately, it's not the account PIN.  It's a 4 digit code for TCP & another 4 digit code for UDP.  

ACE - Professor

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5.5K Messages

3 months ago

What exactly is causing this special need?

ACE - Expert

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35.5K Messages

3 months ago

No idea, then.  As gr8sho asks, why is it that you think you need these ports unblocked?  What is not working when they are "blocked?"  Who says you need them "unblocked?"

3 months ago

I want to update my personal contacts via email inspection using my software.  Software instructions requires ports 25 & 53 to be open on firewall in order to verify emails for my personal contacts.

ACE - Expert

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35.5K Messages

3 months ago

So... you have software on your PC that needs to be able to connect OUT on TCP port 25 and UDP port 53, or you have software on your PC that some other software/users needs to be able to connect IN to your PC on these ports?   It's a fundamental difference and germane to the question you're asking.

3 months ago

needs to be able to connect OUT on TCP port 25 and UDP port 53

ACE - Expert

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35.5K Messages

3 months ago

UDP port 53 is not a problem, it's wide open.

TCP port 25 as a destination port with a source IP of an AT&T consumer gateway is dropped by network management to reduce botnet SPAM.  Depending on how your software works, you should see if it offers use of one of the alternatives (e.g. 587, 465).

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