I used Data Rescue 2 to recover the lost files... it worked! It found my audio files in a hidden folder on the drive named "CBR" in "CBR" there are 2 folders named "Audio" and "Misc" in "Misc" are 2 folders "ETC" and "RSRC" in "ETC" are files named "DS_Store-00001", "DS_Store-00002", "DS_Store-00003", "DS_Store-00004" in "RSRC" are files named "R-0001.rsrc", "R-0002.rsrc", "R-0003.rsrc" in the folder named "Audio" is a folder named "WAV" In the folder "WAV are all the recovered audio files. There are audio files from 3 different session that were all recorded on the same day. Since each session had some tracks with the same name like "LdVoc" there are duplicate files. I had to go through each one to determine which session they belonged to. Once al the files were in the right session's Audio Files Folder, the sesions opened properly. WHAT THE HECK CAUSED THIS? I've been using Protools since it was Sound Designer and I have never seen this occur.