Oooo Yes, this is a "Adobe Reader" problem on windows 10 and 8.1 is everything fine!
And for old Windows OS is that a solution for Thumbnails: ... adobe_pdf_x64_fix
That has to work, for me it works so well on old Windows-XP x64!
But, for PDF preview in "Q-Dir x64" i have to do something :-)!
► ... Improvements in the file preview and integration of the MS Explorer preview window!
► ... How can I change the preview filter settings!
FAQ 59: Updated on: April 15th 2018 13:20