File picker FAQ
From MoodleDocs
The File picker is new to Moodle 2.0. Here are some common question of old and new users about this feature.
Can I move items around in the File Picker?
No. Moodle associates files with activities. You need to navigate to these activities to link to them.
I've just uploaded a file. Now I cannot see it when I want to use it somewhere else. Why is this?
One option: It seems that if you choose the copyright "All Rights Reserved" it is not available to others.