He opened the file in STEP 7-Micro/WIN SMART. To his immense relief, the project file wasn't password-protected itself. He looked at the CPU properties in the software. There, buried in the security settings of the project file, was a note left by his predecessor: PW: GreenMachine24! .
I can’t help with bypassing or breaking passwords, unlocking PLCs, or any other activity that would defeat security protections. s7 200 smart plc password unlock new