Sorry Luca,
never heard this happen before!
This error message will be generated, if the Visio-Interpreter of the MFD operating system finds inconsistent information in the visualization part of your program. This part of the program is stored in a FRAM and it seems, that the two devices, which are showing the described error message, have faulty FRAMs and lost a few bits or bytes of your program.
As I said, I can’t remember this error was ever mentioned since the MFD device is available.
You may want to contact Moeller support and claim to exchange this two devices. May be you can send the devices untouched (do not try to download the program again) and if possible the original project file too, so Moeller eventually can try to investigate, what was going wrong.
Hope you'll have success and best regards
Bernhard Funk