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See this article for some steps that can help share your iTunes library between accounts:
iTunes: How to share music between different accounts on a single computer
All the best,
When you say,"All of the iTunes music is in the Music folder of my user area." Your other accounts may not have permission to reach the music folder.
You can try sharing the folder that contains all of your music so each account has permission to access it.
- Right click music folder
- select "Get Infor"
- select "Shared folder"
- select Enable if necessary.
Hope that works.