I'm using Adobe Acrobat Pro DC 2021 and I enabled the option to see the pdf thumbnails. Most of them can be seen but for a couple of days, I'm not able to see some of them. Besides, sometimes it can't load the preview of thumbnails and most importantly there's one specific file and it got me out of that file which contains some pdfs. But that doesn't happen in all the files that contains pdfs. But when I disable that option, I can go to that file and can see pdfs (but of course, without preview). What should I do?
As you have mentioned above, the thumbnails not loading for some PDFs. Try to repair the application installation and ensure that the application is updated to the latest version. In the application go to Help > Check for updates or Repair Installation.
If the issue still occurs, share the application and OS version. It would be helpful if you can share the screenshot or video of the issue occurring at your end.