The original poster, jcollis217, attempted to copy 70GB of iTunes music to a USB drive but noticed only 39GB was transferred and is seeking help to locate the missing music on their computer. Neemobeer responds by sharing a likely default folder location for iTunes music files on Windows, pointing to "C:\Users\username\My Music\iTunes\". Overall, the thread addresses troubleshooting missing iTunes music files and offers guidance on where to find them on a Windows system.