What will happen if I’m in a conference and send a file?

If you drag-and-drop the file in the conference window or choose “Send File” button from the same window, all the users that are in the conference will receive it. If you want to send the file only to one user, you can select the name from your contact list and then click on “Send File” button from the main window. You can also drag the file onto a user name in your contacts list.