Making folders shared / administrator powers?

I discovered the same problem with my music collection. It is a permission problem and you should click on the "Get Info" tab to see what permissions are set. In my case, the permissions on that folder with set to system read and write and I have to say I really have no idea what system permissions are--it should have been everyone read and write. This is a shared drive off of my Time Capsule. In my case it seems the problem was creating the music folder while mounted to the Time Capsule. Rather than changing the permissions to that folder I created a new folder with the drive mounted to my iMac and the permissions are fine now. They should be user, staff, and everyone read and write--in most cases.

So first check the permissions to the folder that is causing you problems.

 

If you don't mind using the terminal, you may try this:

1. Open the Terminal (/Applications/Utilities/Terminal)

2.- Type the following commands in the Terminal, replacing "your brother's username" with his account name (type exactly, capital letters do matter):

cd /Users/your brother's username
sudo chmod -R a+rX Music

3.- Enter your admin account password when prompted.

This will change permissions on Music and all its subfolders.