Watermarks on notification emails By default, the system generates a watermark label at the bottom of each notification email to allow matching incoming email to existing records. The watermark always includes "Ref:" and a customizable prefix, followed by the auto-numbered identifier of the source record, such as incident, problem, or change request. The default prefix is MSG. For example, Ref:MSG3846157. Watermarks are always generated, but you can configure them to: Create a custom watermark prefix for each instance to prevent accidentally triggering events in the wrong instance. Have custom prefix characters after MSG Be hidden globally Be omitted from individual email messages Inbound email actions might not work properly if watermarks are omitted from email notifications. Without a watermark, inbound email messages cannot be associated with the accumulated comments related to the original incident, and each subsequent notification that is sent is treated as a new incident.Note: Do not use colons (:) in custom watermark prefixes. Colons are a reserved character and may cause the watermark to be ignored.Note: Email clients that use the plain text version of the email still show the watermark. Create a custom watermark prefix for email notificationsBy default, email notifications use the watermark prefix MSG, but you can create a custom watermark prefix.Omit an email notification watermarkYou can omit watermarks on email notifications if you do not want the instance to match the notification to an existing record.Hide email watermarks globallyRather than omitting watermarks, it is possible to hide watermarks on a global basis using HTML markup.