Watermark Collision with existing record

[RuchithaP]

Summary of Issue:
Inbound emails from particular servicenow instance are failing to trigger our 'New' Inbound Action because they are being logged as 'Received Ignored'.

Technical Root Cause:
The incoming email body contains a ServiceNow watermark (Ref:MSGxxxxxxx). Because of this watermark, the email engine automatically classifies the email Type as 'Reply' instead of 'New'. Since it matches an existing record in Email Watermarks(sys_watermark) table in our instance, it skips our 'New' Inbound Action rules entirely and gets ignored and target record is not being created.

Requested Assistance:
We need this inbound email to execute our 'New' Inbound Action logic to create a ticket automatically. Please advise on the best platform practice to prevent this specific sender's email from being locked into a 'Reply' classification based on the watermark.

• Testing Performed: We verified this behaviour in our development instance by temporarily deleting the conflicting watermark record. Once removed, the incoming email was successfully classified as New and processed correctly. (example: MSG1216286)
• Constraint: Deleting or modifying existing production watermarks is not a viable or safe option.

What is the recommended best practice or workaround to prevent a specific sender's email from being locked into a Reply classification based on an external watermark collision?

[Tanushree Maiti]

Hi @RuchithaP 

refer : Inbound emails ignored due to X-ServiceNow-Generated header 

Inbound Email Action- New Incoming Email (no watermark), locate existing incident 

Incoming email classified as reply to 'null' via watermark

https://www.servicenow.com/community/developer-forum/exclude-an-email-from-email-header-rules/m-p/24...

Inbound email actions