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    • Administration Guide

    Home FortiAuthenticator 6.4.1 Administration Guide
    6.4.1
    6.6.2
    6.6.1
    6.6.0
    6.5.5
    6.5.4
    6.5.3
    6.5.2
    6.5.1
    6.5.0
    6.4.10
    6.4.9
    6.4.8
    6.4.7
    6.4.6
    6.4.5
    6.4.4
    6.4.3
    6.4.2
    6.4.1
    6.4.0
    6.3.4
    6.3.3
    6.3.2
    6.3.1
    6.3.0
    6.2.2
    6.2.1
    6.2.0
    6.1.3
    6.1.2
    6.1.1
    6.1.0
    6.0.8
    6.0.7
    6.0.6
    6.0.5
    6.0.4
    6.0.3
    6.0.2
    6.0.1
    6.0.0
    5.5.0
    5.4.0
    5.3.0
    5.2.0
    5.1.0
    5.0.0
    4.3.0
    4.2.1
    4.2.0

    Troubleshooting SMTP server tests

    Troubleshooting SMTP server tests

    The following table describes some of the causes behind SMTP test failure and suggestions on how to solve the causes.

    Cause

    Further diagnostics

    Troubleshooting tips

    Unable to resolve SMTP server's FQDN.

    Verify that the Server name/IP and DNS server settings are set correctly.

    SMTP server did not respond.

    Retry with other standard SMTP ports (25, 587, or 2525).

    If there is no response from any port:

    • Verify that your network settings (interface subnet and static routes) are set properly.

    If there is a response from a different port:

    • SMTP server may be using port X.

    SMTP server's certificate is signed by a non-trusted certificate.

    Import the SMTP server's CA as a trusted CA.

    SMTP server requires a secure connection.

    Enable STARTTLS for Secure connection.

    SMTP server requires authentication.

    Enable Enable authentication and specify the credentials.

    Invalid authentication credentials.

    Verify that you configured the proper credentials.

    SMTP server is unable to reverse resolve the FortiAuthenticator's IP (i.e. no DNS entry) to identify as a valid sender.

    Update your DNS records.

    SMTP server AUTH option must be set to "PLAIN".

    Change your SMTP server authentication options.
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    Troubleshooting SMTP server tests

    Troubleshooting SMTP server tests

    The following table describes some of the causes behind SMTP test failure and suggestions on how to solve the causes.

    Cause

    Further diagnostics

    Troubleshooting tips

    Unable to resolve SMTP server's FQDN.

    Verify that the Server name/IP and DNS server settings are set correctly.

    SMTP server did not respond.

    Retry with other standard SMTP ports (25, 587, or 2525).

    If there is no response from any port:

    • Verify that your network settings (interface subnet and static routes) are set properly.

    If there is a response from a different port:

    • SMTP server may be using port X.

    SMTP server's certificate is signed by a non-trusted certificate.

    Import the SMTP server's CA as a trusted CA.

    SMTP server requires a secure connection.

    Enable STARTTLS for Secure connection.

    SMTP server requires authentication.

    Enable Enable authentication and specify the credentials.

    Invalid authentication credentials.

    Verify that you configured the proper credentials.

    SMTP server is unable to reverse resolve the FortiAuthenticator's IP (i.e. no DNS entry) to identify as a valid sender.

    Update your DNS records.

    SMTP server AUTH option must be set to "PLAIN".

    Change your SMTP server authentication options.
    Previous
    Next