E_LIC_LICENSE_SIGN_ERROR
This is my first time using Adobe Digital Edition and hopefully my last. I'm trying to add a book which is in an acsm file to the library but I keep getting this error message. I'm on Windows 10 if that helps.

I've tried troubleshooting the issue with these solutions:
- Erasing the authorization and re-authorizing it
- Going into regedit, deleting the adept activation, then reauthorizing it
- Restarting my computer
- Making sure I have the latest adobe software
- Reinstalling Adobe Digital Editions
- Trying a previous edition software
My issue still isn't resolved after all these methods I've tried. I'd love a solution to this so I can read the book I need for school. Can someone from Adobe please assit me with this?
