I am presuming you mean there is a 'lock' on the folder icon. If so you need to change the "Permissions" to access it. Hopefully the following should work:
- Right-click the folder or drive that has a lock icon and click "Properties"
- Click on the "Security" tab, then click "Edit" to change permissions. Click "Add", another box will open with a text field
- In the text field for "Object Name", enter in "Users" (without quotations), click "OK"
- Click "Apply", "OK", and if it works properly, the padlock next to the icons should be gone.