from the manual - "
• IBAG inverter
The IBAG inverter is not disconnected by the mains connection of the
cutting table.
Do not remove the cover of this unit until the mains connection has
been removed from the socket outlet for the IBAG inverter"
It looks like this "IBAG inverter" is plugged into the wall as well as into the computer? (I have never seen you machine, I JUST DID A GOOGLE SEARCH for you...) To me it sounds like a computer is supposed to control a dangerous item with its own power (the IBAG inverter) and the computer is not getting a signal saying it has control over the IBAG inverter - so you will not be hurt it is giving you a warning.
I would check any connection and maybe relay that goes between the main board and this IBAG Inverter. (if this inverter has its own computer, maybe try unplugging it and a hard restart - the error indicates the computer could not connect to the inverter - is the inverter plugged in?)