I am running Windows 10, and installed Acid 9 free trial, but when I click on one of my almost 1,500 loops, it says it's not associated with this program, and asks if I want to open the program associated with it. It seems that back when I was running Acid 2.0, the loops could be 'acidized' or associated with the program somehow. I looked through all menus, and checked ms windows file preferences and advance, and did not see any way to associate the files with the new Acid 9, and not with Audacity, which probably does this when it's installed. Yes I installed that first, and no I didn't like it at all. So anyway not what my Acid 9 is installed and registered, it will not even preview any of my loops (.wav) all proper acid loops, but it won't preview or place them in the song, when I double click. How can I get the loops back and associated with the Acid family of music composing software?

Same here. but in my case, its MP3s. In my case, on two "powerful" machines, same issue, MP3s will not be read by Acid pro. I have to take them into Wavelab, convert them back into Wave, so I can open them in Acid. Workflow killer and Magix does not have a solution that has worked for me so far.