How do I flatten a PDF to make it more compatible?

Depending on the way a PDF file was created, some PDF files can have layers for different elements in the file. This can cause some parts of a PDF file to not display correctly in some apps. To make sure that all parts of a PDF file are visible and display correctly you can flatten all the layers in the PDF file. The steps below are done using Adobe Acrobat Pro DC on a Mac, similar steps should be available on a Windows machine.

1. Open the PDF file using Adobe Acrobat Pro DC.
2. Choose File > Export To > PostScript.
3. In the Save dialog, leave the Format set to PostScript.
4. Also in the Save dialog, under Settings, leave the Printer Description File set to Device Independent.
5. Click on Save which will save the file with a .ps suffix for PostScript.
6. Launch Adobe Acrobat Pro DC and choose File > Open…
7. In the Open dialog, change the Show setting to All Files.
8. Open the .ps file you saved previously.
9. Save the new flattened PDF to a location.