Download and install Windows XP Service Pack 2 Support Tools. When installing be sure to check the box for complete installation.
Click on Windows Start button and open the Run dialogue box. Enter the text "dupfinder" in the text box and press the Enter key.
Browse to find the folder you wish to search for duplicate music files. In Windows it is usually My Music.
Click the Start Search button. Duplicate files appear sorted by name.
Carefully review the duplicate files, and delete a file only if you are sure it is truly redundant.
Start Windows Media Player. The deleted files no longer appear.
Start iTunes and open the music library view.
Select "Display Duplicates" from the File menu. iTunes shows you a list of songs with the same name. However, some of these might be a remix or the same music performed by a different artist. Use this option only when there are few duplicate files.
Press the Shift key and select "Display Exact Duplicates" from the File menu. For Mac users, press the Option key instead of the Shift key. iTunes displays a list of songs with the same name plus other features.
Sort the list of exact duplicates by name, comparing each according to its other features, such as length, date modified, album name and date added.
Delete files with care. In iTunes, there is an option of viewing the duplicate files in Windows Explorer to determine if in fact there are two physical files.
Download and install a product that compares music files. One such product is Audio Comparer.
Decide which folders to search for duplicate music files. Or, search your whole music library.
Search for close matches or exact matches. Searching for close matches is fast but only identifies files with the same name or file information. An exact match implies that music is digitally the same from start to finish, and requires more time to analyze all files to be compared.
Start the search process. This might take awhile. For example, if you designated an exact match, Audio Comparer listens to each file in order to create an audio signature--a snapshot of a song's actual audio properties--for each music file.
Examine the list of potential duplicates carefully. You can listen to part or all of the files suggested as duplicates. Be sure they are really duplicates, not a remix or a performance by another artist, before deleting.