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    Aleph 22: Mailing fails with error 'Error "421 4.3.2 The maximum number of concurrent connections has exceeded a limit, closing transmission channel"

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    • Article Type: General
    • Product: Aleph
    • Product Version: 22

    Problem Symptoms:
    When mailing the following error occurs in the GUI client:
    Unable to Find Id: 421: SMTP server not avalable in File: message.dat

    When trying to telnet to the Mailserver on port 25 the error "421 4.3.2 The maximum number of concurrent connections has exceeded a limit, closing transmission channel"
    is displayed

    Cause:
    Secure SMTP (SSL) creates parallel sessions

    Resolution:
    Configure the mail server parameter
    MaxInboundConnectionPerSource to 1000 or even to unlimited.

    Category: Installation & Upgrades (500) - ALEPH

    Subject: Installation - ALEPH

    • Article last edited: 9/11/2014