Internet Creations has never observed an instance where Email to Case Premium actually duplicated an email, comment or case without another variable in play. Issues related to duplicates are typically found to be misconfigurations either on the forwarding email server or from an improper Email to Case Premium setup.
Please review the following items in order to see if one fits the situation you're facing.
1. If you've noticed that an inbound email created two cases:
- Ask your email server administrator to confirm the path of the inbound email received. In many instances, we've found that some Email to Case Premium customers have encountered a duplicate problem because they are forwarding inbound emails through both Email to Case Premium & standard Email-to-Case.
- For example, if an inbound email is sent to firstname.lastname@example.org, these emails should only be forwarded to the routing address specified in green on the first page of the Email to Case Premium setup wizard. These emails should NOT be forwarded to the standard Email-to-Case routing address.
- Look at the email headers of the related Email Message objects and compare the Email Message ID.
- From the Emails related list, open each email and click Click here to view original email headers. Inspect the email message headers to determine if the Email Message IDs are unique or not. Note: You might need to enable the Save Inbound Email Headers setting first, and resend a test once enabled.
- If the Email Message IDs are unique in each suspect duplicate, contact your email server administrator to investigate why multiple emails were forwarded to Salesforce.
- If sending an email directly to a Email to Case Premium routing address does not result in duplication, contact your email server administrator to investigate why multiple emails were forwarded to Salesforce.
- If the Email Message IDs are the same in each suspect duplicate or sending an email directly to the routing address results in a duplicate, please contact us for assistance.
2. If you've noticed that a duplicate email, comment and/or case was created after using the New Comment page or Answer Customer action:
- Check to see if the outbound email created from the New Comment page or Answer Customer action was addressed to a support address that routes back into Salesforce.
- For example, if cases can be created by sending emails to email@example.com, outbound emails from Salesforce should NOT be addresses to firstname.lastname@example.org (as that email will route back into Salesforce and cause duplication).
- If this is found to be the root cause, be sure to check your Case Creation Settings to ensure that each of your support addresses have been defined. Support addresses which are defined here will be automatically removed from the Additional To/CC lines on the New Comment page (in order to help prevent duplicate issues).
Note: Internet Creations cannot troubleshoot email forwarding rules on mail servers/services like Google Apps, MS Exchange or MS Office 365