Hey, were you ever able to resolve this problem? I'm having the same problem.
I checked the following six registry entries
The "default" values all point to the right executable like this: "C:\Program Files\Adobe\Adobe Digital Editions 3.0\digitaleditions.exe" "%1"
Thanks for your attention,
I'm having the same problem - can't associate acsm with ADE - just with Adobe Reader.
Can't seem to find a solution anywhere here.
Hi, I've just spent a frustrating 2 days trying to associate ADE 4.5.9 with .acsm files after upgrading - and here's the solution that worked for me with Windows 10. Can't guarantee it'll work on other Windows versions but here it is, short and simple.
1. Click start
2. in Search box enter "*.acsm* without the quotes
3. right click on any .acsm file and select "Open with"
4. in "Open with" window select ADE and tick the box "Always open with" and click "OK".
5. ADE should open and the book should appear
6. Go to your online library and download an ebook
7. ADE should now open and fulfil the book.
Hope this helps.