CiviMailing Fails with duplicate entry error before sending

When CiviMail is scheduled to send mails with Include Groups and Exclude groups selected. The mailing fails with the following error.

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Sorry. A non-recoverable error has occurred. <p></p>
<p>Database Error Code: Duplicate entry '23' for key 1, 1062</p>
<p><a href="http://abc.org/administrator/" title="Main Menu">Return to CiviCRM menu.</a></p>
</dd>
</dl>
</div>

</div>
</body>
</html><p>Error Details:</p><p><pre>Array
(
[callback] => Array
(
[0] => CRM_Core_Error
[1] => handle
)

[code] => -5
[message] => DB Error: already exists
[mode] => 16
[debug_info] => INSERT INTO X_43 (contact_id)
SELECT civicrm_group_contact.contact_id
FROM civicrm_group_contact
INNER JOIN civicrm_mailing_group
ON civicrm_group_contact.group_id = civicrm_mailing_group.entity_id AND civicrm_mailing_group.entity_table = 'civicrm_group'
WHERE
civicrm_mailing_group.mailing_id = 40
AND civicrm_group_contact.status = 'Added'
AND civicrm_mailing_group.group_type = 'Exclude' [nativecode=1062 ** Duplicate entry '23' for key 1]
[type] => DB_Error
[user_info] => INSERT INTO X_43 (contact_id)
SELECT civicrm_group_contact.contact_id
FROM civicrm_group_contact
INNER JOIN civicrm_mailing_group
ON civicrm_group_contact.group_id = civicrm_mailing_group.entity_id AND civicrm_mailing_group.entity_table = 'civicrm_group'
WHERE
civicrm_mailing_group.mailing_id = 40
AND civicrm_group_contact.status = 'Added'
AND civicrm_mailing_group.group_type = 'Exclude' [nativecode=1062 ** Duplicate entry '23' for key 1]
[to_string] => [db_error: message="DB Error: already exists" code=-5 mode=callback callback=CRM_Core_Error::handle prefix="" info="INSERT INTO X_43 (contact_id)
SELECT civicrm_group_contact.contact_id
FROM civicrm_group_contact
INNER JOIN civicrm_mailing_group
ON civicrm_group_contact.group_id = civicrm_mailing_group.entity_id AND civicrm_mailing_group.entity_table = 'civicrm_group'
WHERE
civicrm_mailing_group.mailing_id = 40
AND civicrm_group_contact.status = 'Added'
AND civicrm_mailing_group.group_type = 'Exclude' [nativecode=1062 ** Duplicate entry '23' for key 1]"]
)
</pre></p><p></p>
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