There is no "master password" to bypass security without losing the program. If you cannot contact the original programmer or OEM for the password, use these standard methods to clear the device. Method 1: Using STEP 7-Micro/WIN SMART Software
Use the Wipeout.exe tool (found on the original installation CD) to reset the PLC to its factory state. This also resets the communication baud rate and network address. Security Warning s7 200 smart plc password unlock new
If you can access the PLC but specific code blocks (POUs) are locked, this is often "Know-how protection". Setting up block know-how protection - STEP 7 There is no "master password" to bypass security
Password required for both uploading and downloading. This also resets the communication baud rate and
High – can brick the CPU if voltage levels wrong (1.8V or 3.3V? depends on revision). Success rate: ~95% if done correctly. Use case: Mass unlocking for refurbishing units.