Good morning, colleagues. My problem is that when I press F5, I can't see the Maintenance screen. I was reading the maintenance manual, and it says I should enter DOS, type PFM, press Enter, and a program should run that displays machine values ??in real time, but I've also tried that and haven't been successful. It seems I'm missing some software on my hard drive. Could someone please help me solve this problem? I look forward to your responses. Thank you very much.