"An item with the same key has already been added" error message in Marketing Cloud Tracking
|Knowledge Article Number||000220865|
Exporting bounces displays a blank page in Internet Explorer and an XML Parse error in Firefox. Applog error contains: "An item with the same key has already been added."
This issue occurs when a Profile Attribute has been created with the same name as a System Attribute that's used in the Export. For example, a Profile Attribute called "Undelivered Time" will cause this behavior when attempting to export bounces.
To resolve this error, rename the Attribute to something else and the Export will start working again.