This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
You still have an OutputStream to the file open. That means that Windows disallows renaming, deleting, etc. You can't delete or rename a file in Java unless all streams etc to it are closed. Also, the file to rename to cannot exist yet.