How can I apply PreFlight fixes to specific pages and not the entire document?

[Allegra Southfield]

The "Preflight only pages" boxes under "Further Options" does not work. I tried to convert only a couple of pages to Grayscale but it converts the entire document instead.

[Dov Isaacs · Accepted solution]

You don't mention which version of Acrobat your are running, but support for specifying page ranges is by design not available for all profiles, single checks, and/or single fixups. Convert to Grayscale is a profile that doesn't allow for page range specification. There are reasons for such restrictions including the fact that in PDF, many objects are shared between pages (for example, a single image may be defined once within the PDF file but referenced multiple times).

          - Dov

[Allegra Southfield]

Thanks for the answer. I am running version 2019 - Acrobat Pro DC, by the way.

[Stephen_A_Marsh]

Be sure to use the “Preserve Black” option.

A hack is to duplicate the original PDF and remove all but the pages that require changing. Run the preflight/fixes etc and save. Then use the replace pages feature to swap out the pages. I would then recommend performing a save and then a “save as” to another location and compare the file size. The save as step is to clean up the file and potentially reduce file size (file size is likely to grow for the reasons that Dov mentions above).