Symptom
Other users can see the contents of your Drop Box folder but are not able to copy files to it.
Solution
This issue does not affect users created after installation, only the first user created by the Setup Assistant. Follow these steps to set the correct privileges:
1. Click the Finder icon in the Dock.
2. Go to the Home directory of the affected user, and locate the Public folder.
3. Open the Public folder and select the folder Drop Box.
4. Choose "Vis info" from the Arkiv menu.
5. Choose Rettigheter from the drop-down menu in the window that appears.
6. Set Gruppe and Alle to "Kun skrive (mottaksmappe)".
7. Close the window.
To verify that the changes were made, either log in as another user or log on to the computer from another computer on the network.
Apple may address this issue in a future update to Mac OS X.