These fields must be selected in the folder definition in the CA Output Management Web Viewer AdminTool to be visible on the Report Criteria Screen.
Set it for each folder in the folder properties. On the definition panel, near the bottom, there is an option: Display Mode and DistID Switching (CA View Only).
Check this and it will be implemented immediately after having the user reopen the browser.
In Web Viewer two boxes will be displayed on the Report Criteria screen under the Folder Filter Settings. There will be a dropdown box for Mode and a box for Dist ID.