OK guys I think I have a new one, I have debugged my collection - 100%mastery, duplicates, persistent ID, max 5 (mostly NO DD & sometimes bonus and rarely metronome) I have been meticulous with this because I don't want to do it again or at least not anytime soon (fingers crossed). I have removed all duplicates and all backups from those folders in the CFSM (program files x86 section) I have scanned the CFSM program with an empty dlc folder to delete the ghost files (don't know the technical name (probably cache or cookies, I'm not a techie) Once I had the program telling me it was empty I then loaded my fixed cdlc"s back in the dlc folder and rescanned all files show up and show no errors (i.e. max 5, duplicates, 100% bug, persistent ID etc.) only in the program no duplicates show either in the duplicates tab nor in the long file name,, but in the actual DLC folder I can see many files which have the .dup ending. for instance (Bob Marley stir it up v2 .psarc.dup and Bob Marley stir it up v3.psarc) and they have different file names and are not persistent ID 'S any ideas ? IMPORTANT Can I just go in the DLC folder and just manually rename the file by just removing the.dup extension or will this cause problems with the game or file ?