Right Click on the epub file.
Choose open with.
Choose Digital Edition.
Activate the option that it was allways with the programm.
Then is should work.
Thank you for your reply. Unfortunately this doesn't seem to work. When I try to open with the choice of Digital Edition and small box appears with the words "Error! Check Activation".
Close all applications.
Choose Start > Run.
In the Open text box, type regedit and then press Enter. The Registry Editor opens.
In the left pane of the Registry Editor, locate the following registry key: HKEY_CURRENT_USER\Software\Adobe\Adept
Right-click the Adept key and choose Delete.
In the Confirm Key Delete dialog, click OK.
Close the Registry Editor.
Open Adobe Digital Editions and reauthorize.
I also cannot open an epub Indesign file in Digital Editions unless I export as a 2.0 epub.
I have ADE 4.57 and 2018 InDesign CC. I/ trying to create an epub for a 335-page book.
Need to find errors, etc and I must have a 3.0 file. Does the Registry correction work for this