EPUB passes latest EPUB-Checker, but won't open in latest ADE.

[#1]

EPUB passes latest EPUB-Checker, but won't open in latest ADE.

I have run the debugger in Calibre, and I have run it through EPUB-Checker - all latest versions of each.

I have tried to open several EPubs that I know are good and have opened in ADE before, and they won't open.

It just spins and in the title bar it says (Not Responding)

Second issue - I can't authorize ADE - same as another poster a few hours ago.

[#2]

fixed auth issue with

1. Quit Adobe Digital Edition.
   
   2. Choose Start > Search for regedit (On Windows 10: it’s in c:\Windows
   directory)
   
   3. Right click on regedit, ans select “Run as admininstrator”
   
   4.In the left pane of the Registry Editor, locate the following registry key:
   HKEY_CURRENT_USER\Software\Adobe\Adept
   
   5. Select “Adept” , right click on it and select “Delete”
   
   6. In the Confirm Key Delete dialog, click OK.
   
   7. Close the Registry Editor.
   
   8. Open Adobe Digital Editions and reauthorize (Help->Authorize Computer…).