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  • Question

  • I can't use port 25 in pop3 settings. The following is the image of the receive conntector setting.

    I really need to use port 25 because the existing application and the user are using port 25, please don't suggest another port. thanks

    Tuesday, September 29, 2020 10:16 AM

All replies

  • Hi,

    If you have POP3 or IMAP4 clients that can only send SMTP email on port 25, you can configure port 25 on the "Client Frontend <Server name>" Receive connector to allow clients to send authenticated SMTP email. However, because port 25 is also configured on the "Client Frontend <Server name>" Receive connector for email from external SMTP servers, you'll need to modify the local IP addresses that are used to listen on port 25 on one or both of the connectors. For more information, see Receive connector local address bindings.

    Actually this Exchange Server Development forum is NOT for asking such questions, the previous TechNet Exchange forum has been migrated to Q&A forum, you can post your issues there for better support.


    Eric Yin

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    Wednesday, September 30, 2020 5:48 AM