I've installed Xubuntu 16.04 on my new laptop and I don't have multiple desktops and desktop switcher also CTRL+ALT+ARROWS shortcuts don't work.
32 Answers
You have to specify the required number of desktops in System Settings => Workspaces, after add the desktop switcher to your panel.
You can make by following below steps on Ubuntu 16.04:
System Settings → Appearance
Appearance → Behaviour
enable workspaces option.