Did you perform a switching operation from the machine's operation panel?
Is the machine correctly connected to a wired LAN or wireless LAN?
Check whether the machine is correctly connected to a wired LAN or wireless LAN.
NOTE
Note that if you change the connection setting to wireless LAN connection from other setting (USB or wired LAN connection), you need to uninstall the drivers from your computer and then reinstall them. For more information, see the manuals for the relevant drivers on the online manual website.