DOWNLOADING AN .ACSM FILE CRASHES ADE. WHY?

When I download the .acsm file, ADE freezes. Why? I have uninstalled/downloaded every version of ADE from 3.0 and up. The app opens without any problem. I have authorized/unauthorized, rebooted, etc. until I am blue in the face. If I connect my Kobo to ADE before downloading the .acsm file, it freezes ADE. Can anyone give me an explanation.