Key Filters allow efficient filtering of the files displayed in the current view in Outlook and DMF Explorer based on one or more of the files metadata values.
Applying a Key Filter
To apply a Key Filter to the items in the current view, click the 
button on the ribbon or File List Toolbar and select the required values from the list of available key filters.
You can also apply a filter to any other column from the filter dialog or by clicking on the column header in the list view.
MacroView DMF and Message also support the simultaneous use of key filters and metadata navigation.
Clearing a Key Filter
Any applied filters, including Key Filters, are cleared when you click the 
button on the ribbon or the File List Toolbar.
To clear a column filter without removing any key filters, click on filter button on the column header of the filtered column and then click clear.
Defining a Key Filter in SharePoint
Authorised users can define Key Filters in SharePoint for libraries where metadata navigation is also enabled. A key filter can be added for the following column types:
- Content Type
- Number
- Choice
- Date
- Person / group
- Managed Metadata (base don a hierarchical term set)
To add a key filter to a library, open Library Settings in the browser and select the Metadata Navigation page. Then add the required column a key filters.
Version support
Key filter functionality is supported in the following versions of MacroView DMF and Message:
- On-premises SharePoint: DMF / Message 7.4 or later
- SharePoint Online (Office 365): DMF / Message 8.5.1074 or later
Additional notes
- Key filters are not supported when viewing a Group by View on SharePoint Online (Office 365) or Client Side Only servers.