Some of the users have open resources, disconnecting these users may cause loss of data. Are you sure you want to disconnect all users from all connected resources?
When you choose to disconnect all users from all resources, you run a risk that these users will lose changes that they have made to shared files. Consequently, Server Manager presents you with this confirmation message.
If you are sure you want to disconnect all users from all shares, click Yes. If not, click No. Then, before selecting this option again, alert all users that they are about to be disconnected.