I found this in knowledge base of Sony: Knowledge Article C333142 How to delete song files that have been converted (optimized) to the OpenMG™ format in the SonicStage® 2.x software. Follow this procedure to delete a file that has been converted to the OpenMG™ format in the SonicStage® software. 1. In the SonicStage window, click to select a track. 2. Right-click the track and select Properties from the menu. 3. In the Track Properties window, click the File Info tab. 4. Under File format, click to select the OpenMG file. NOTE: To verify that the file is an optimized file, under Location, the file should be in the Optimized Files folder. 5. Click the Delete File button. Is this possible made for multiple files automaticly?