Canon MX920 Printer Offline could be brought on by the Windows Firewall. Click Start > Control Panel > Security Center > Windows Firewall to momentarily disable the Windows Firewall. Additionally, select OFF, then click OK. Open the Canon IJ Network Tool to check communication after it has been disabled.
To do this, go to Start > All Programs > Canon IJ Network Utilities > Canon IJ Network Tool > Canon IJ Network Tool. Click Utility after selecting the device. Additionally, choose Network from the pop-up option. Next, select the device and click Network Settings.