Checking Email Wirelessly With Apple iPhone



  • Does anyone know if the Apple iPhone uses a specific protocol to check Gmail email by wireless?  I've enabled the following firewall rules on my wireless:
    1)  TCP/UDP port 53
    2)  HTTP port 80
    3)  HTTPS port 443
    4)  UDP port 123

    I just noticed that my iPhone is not checking my Gmail email as it should.  Any suggestions?

    Thank you.


  • LAYER 8 Netgate

    Try 110, 143, 993, and 995. (pop3, imap, imaps, and pop3s)

    And 25, and 587 for sending. (SMTP and SMTP Submit. You probably only need 587 there.)

    This is not just gmail/iphone, but any SMTP/POP3/IMAP mail server/client.

    It looks like gmail does not accept pop3 connections on 110 +STARTTLS and you must use TLS on port 995 instead.

    The same probably applies to IMAP. They do appear to accept authenticated STARTTLS connection on port 25 in addition to 587.



  • I thought about adding IMAP but I was able to get to Gmail from my wireless Macbook Pro; that's getting to it via the web URL though.  As well, from my wired network, I can get to Gmail with no issues; from the web URL.

    I'm using the iOS built in configuration to check for my Gmail email, not the Gmail app.



  • Ok, so I added TCP ports 143 and 993 and I was able to get to my Gmail email with the built in iOS email check.  I thought port 143 was TCP/UDP though.  The straight TCP for 143 appeared to work.


  • LAYER 8 Netgate

    Yeah. That is pop3/imap, not https.

    Mine looks like it's using IPv6 IMAPS on port 993 to access the gmail mailbox.

    WAN tcp 2600:8801:x❌x❌x:add4[53869] -> 2607:f8b0:400e:c04::6d[993] ESTABLISHED:ESTABLISHED 24 / 23 3 KiB / 4 KiB


  • LAYER 8 Netgate

    None of this is UDP. It's all TCP.

    110 is POP3, possibly supporting STARTTLS
    143 is IMAP, possibly supporting STARTTLS
    993 is IMAPS, requiring a TLS connection
    995 is POP3S, requiring a TLS connection



  • Looks like I'm back in business.  Thank you for taking time out to help.  I appreciate it!


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