Cannot Delete xxx xxx: The Directory Is Not Empty Windows XP

Harmonica Bob

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Feb 25, 2010
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18,510
Hello, I get this message [Cannot Delete xxx xxx: The Directory Is Not Empty Windows XP]when I try too delete a new folder in my "E" Drive (Where I store all my music, Back-Up, Excel, Word, PDF Ect.
 

Harmonica Bob

Distinguished
Feb 25, 2010
6
0
18,510

How can I tell if "Or any other files inside the folder is not used by system."? Thankyou, Newcomer