Email-to-Case sometimes generates bounce-back emails with "NULL" content. These emails are often generated by automated emails sent to an email-to-case address.
Here is an example error email:
From: support@emea.salesforce.com [mailto:support@emea.salesforce.com] Sent: 10 June 2013 22:32 To: SFDC Admin Subject: Email-to-Case: Error(s) encountered while processing The following errors were encountered while processing an incoming email: LIMIT_EXCEEDED : A loop was detected in Email-to-Case processing
From: ********************************* (null) Sent: Mon Jun 10 21:31:22 GMT 2023 To: ****************************************** Subject: TEST null
The Email-to-Case algorithm looks at the subject, sender and body to detect looping. After receiving more than 15 emails within 60 seconds with those fields matching, we will prevent additional emails from creating cases.
A workaround would be to make sure that the emails which are generated should either have a unique subject or unique body to prevent this from happening.
For more information specific to email loops, see Email to Case: On Demand Best Practice for Email Retention and Preventing Email Loops.
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