I hope this gets rid of the content preparation progress window:
Disable the screen reader options in Adobe Acrobat:
Within Adobe Acrobat, go to “Edit > Preferences > Reading” Locate the “Screen Reader Options” section. In the ‘Page vs Document’ dropdown box choose “Only read the currently visible pages”, and uncheck “Confirm before tagging documents”.
- [WayBack] Adobe Acrobat prompts that the document is untagged and must be prepared for reading
- [WayBack] Adobe Acrobat 11 – Content Preparation Progress window – Spiceworks
- [WayBack] How do I disable accessibility features??? | Adobe Community
–jeroen