Cause

The same drilling pattern name was assigned to several drilling patterns. The placeholder <x> in the message specifies the drilling pattern name that exists several times.

Solution

1. Locate the drilling pattern name existing several times in the project using the Go to (graphic) function from the popup menu in the Message management dialog.
2. Change the names one after the other in the dialog Properties <...> of the associated drilling pattern names so that each name occurs only once in the project.
3. Click [OK] to apply the change respectively.
4. Start any check run in order to delete the message.
5. Create the drilling pattern again by using the menu items Utilities > Generate drilling patterns / outlines > Automatically from macro project.