Since the DocuWare Version 6.9 new dialogs are used in the search masks and filters in the DocuWare Administration.
While you're trying to create an index filter in the file cabinet profiles, the index filter is opened to configure, but only an empty page or an error message "Page cannot be loaded" is displayed (see screenshot Empty indexfilter).

Empty indexfilter

If you enter the URL of the Web Configuration - http://Servername/DocuWare/SettingsUI - in the browser you get the message that the link is blocked (see screenshot Blocked through the browser).

Blocked through the browser

Add the URL of the Web Configuration to the Trusted Zones of your browser.
If the buttons in the configuration page of the filter are displayed empty please refer to following FAQ: