Closed Digital Edition.
Rename the My Digital Edition Folder under your Documents to My Digital Edition.old.
Then start Digital Edition again and download a ebook.
I just did what you have suggested here.
The problem persists.
Only with one eBook file?
Well, I was just now able to open a 3rd party commerical epub, no problem.
I am unable to open epubs that I have exported from InDesign.
This includes old epubs I have exported from InDesign that always opened in ADE without any problem.
This includes new epubs exported from InDesign that have passed epub validation checking.
In this case would say that problem with the export file. Better you open a thead for InDesign. If other files work Digital Edition are fine.
I'll do that, thanks.