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SSL connect error 0 null error on All Passive Inputs


QAID # 22304

Question / Problem:

All passive inputs are in the 'ERROR' state with the following error, "SSL_connect error 0 (null)". What is the cause of this error

Answer / Solution:

The returned null value in the "SSL_connect error 0 (null)" error normally indicates that the connection was closed by the 'other' end. Usually this is the mail server but it could be some infrastructure that's placed in between the MC and the mail server.

These are some items to investigate when encountering the issue:

  • Check the mail server. Is there possibly a limit set on the amount of IMAP connections per mailbox or per server?
  • Check/setup IMAP logs on the Exchange server.
  • Are accounts getting temporarily locked?
  • When the issue is occurring, from the MC machine (and possibly other machines), see if you can connect to the same IMAP mailboxes with another application (e.g. Thunderbird) using the same connection settings.

Applies to:

Product Version
KIC 2.5
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