If you give a pointer to their website we may be able to see why it doesn't work for you any longer.
It could be that ADE (digital editions) has somehow lost its association with .acsm files;
these are the token files you download for DRM loans and purchaces.
ADE opens these, does the DRM check, and if all goes well downloads the 'real' .epub file.
Public domain books don't need the extra step, you just download the .epub and read it.
- opening ADE,
- finding a library book you have just borrowed in your file manager (eg Windows Explorer, Mac Finder)
The book will probably be in your Documents/Downloads directory,
and have a name related to the book title and have an extention of .acsm
- drag the book from the file manager onto ADE
- ADE should open it.
If that works, it confirms that the missing file association is likely. See ~~~ at end of post.
If not, something else is wrong. Post back with any extra information you can think of.
Just checked the library to make sure it still had standard .epub books.
One possibility is that with the new layout you might have accidentally chosen the wrong book format when you borrowed?
Sometimes the registration of ADE to Windows as the default hander for .acsm and .epub files does not work;
that is what causes the double-click in Explorer to fail; and usually prevents opening from the browser as well.
especially in Windows 8/8.1, and maybe 7;
this appears to be a bug in Windows (for once not a bug in ADE).
Two possible ways round it.
First, try to force it in Explorer
Right-click on a .epub file (and repeat entire sequence for .acsm if necessary)
Select 'open with' if on the list, 'open' if not.
Select 'choose default program'
Select ADE if it is on the list,
If not select 'more options' and navigate to the ADE executable (may be at C:\Program Files\Adobe\Adobe Digital Editions\digitaleditions.exe)
Now .epub/.acsm files should be associated with ADE, and double-clicking should work.
Sometimes, Windows allows you to go through all that, but then refuses to make the association you have asked for.
In that case, the only way I know is to use a third party file association program.