on iMac 10.13.6 and Adobe Reader DC version 2020.006. cannot open most pdfs that I need to use

[philf74412527]

on iMac 10.13.6 and Adobe Reader DC version 2020.006. cannot open most pdfs that I need to use for school projects.  One in ten opens fine, the rest appear as blank screens.  They open as blank, not too useful!

[Peru Bob]

I've moved this from the poorly named Community Help forum (which is the forum for issues using the forums) to the Acrobat Reader forum so that proper help can be offered.