It's steel the same.Keep the power button pressed and quickly select "Turn on Airplane Mode" - This should stop the error messages and let you interact with the phone.
Use the "Network" App from the Play Store to change your phone into GSM mode. It will keep giving you an error until you get from CDMA - > GSM mode.
You can also try resetting the phone completely using recovery mode - that helps sometimes get rid of the message. Resetting the phone will not reset build.prop.
Found this thread :
http://www.andromods.com/fix-troubl...-android-systemui-has-stopped-chromecast.html