Acrobat requires you to have a file open in the document pane in order to run a preflight check unless you use a batch sequence or droplet. To preflight a document, be certain a file is open and click the Preflight tool in the Print Production toolbar. In the scrollable and resizable window, you see a number of preinstalled profiles listed with a description for the kind of preflighting each profile performs. Use the scroll bar on the right side of the window to display additional profiles, and open & close the various disclosure triangles. If the number of items gets too many, try using the Show & search/filter options.
The Options menu contains a number of menu choices for editing profiles, importing and exporting profiles, and creating profile reports.
If a profile exists containing the conditions you want to check, select a profile and click the Analyze button. After analyzing a file, a summary report appears in the Results tab in the Preflight window. Any errors in the file are reported in the summary. The summary report is listed in a hierarchy with subnotations listed under parent categories. Click the icon to the left of each category to expand the list.
If you see errors reported after preflighting a file, you need to fix the problems either in Acrobat using Preflight’s FixUps, the Print Production tools or back in the original authoring program, and recreate the PDF file.