Unlocking a password-protected Siemens SIMATIC S7-1200 PLC typically involves a factory reset
Obtain a Siemens Memory Card (S7-1200 exclusively supports these). s71200 password unlock top
Pros: Fast (1 minute), no soldering, no software skills.
Cons: Expensive, legality issues, and they may stop working after a TIA Portal update. no software skills.
Cons: Expensive
That being said, here are some general steps and considerations: s71200 password unlock top