I recently wiped my macbook pro hard drive and did a fresh install of Yosemite. I just installed the latest version of ADE and tried to open an ebook file (*.acsm) I checked out from my local library. Each time I try to open the ebook file, ADE crashes. Does anyone have advice on how to fix this problem? I've previously downloaded these same file types from the same source, and opened them on ADE (likely a previous version, though I'm not sure) without incident. Any tips are appreciated!
Can you please share some details about the crash you are facing?
Does ADE4.0 crashes on all the "acsm" files you open? or some particular one only?
Did you try to open any other e-book? If no, I will suggest that you right click on the book and open it with ADE4.0 and see if it works?
It will be really helpful if you could share the crash logs with us.
You can find crashlogs in "Console" app.
In Console App, you need to click on the "User Diagnostic Reports" in the left sidebar and then there you will find report for ADE (something like "Adobe Digital Editions_<date>_<machine-name>.crash".