We need a way to identify contacts who haven't opened any past emails in order to remove them from future ones. Whilst we can get a list from an individual campaign, there is currently no way of finding a master list of contacts with poor engagement. Our contacts are often spread across campaigns, and so there is no practical way to identify the ones we should be removing.

In an ideal world, uploading a spreadsheet would identify contacts with poor engagment, so that these can be removed.

Alternatively, a way to blacklisting contacts with poor engagement would be good (similar effect to unsubsribing, but distinguishable and reversable).

This is partly to ensure we don't waste outbox space on poor targets, and partly to ensure good email practice and improve our rating with Outlook.