Connect your PC to the S7-200 SMART PLC via Ethernet. Go Online: Establish communication with the PLC.
Open Notepad on your PC and create a completely blank text file named exactly S7_JOB.S7S .
Attempting to extract data using unauthorized exploitation tools can corrupt the system bootloader or core system blocks. This damages the internal flash memory, rendering the PLC permanently inoperable ("bricked").
For CPUs that are completely inaccessible via software, you can use a MicroSD card to perform a firmware update or a memory reset. Format a MicroSD card (FAT32).
After clicking "Clear," you must perform a physical power cycle on the CPU within 60 seconds. A simple software restart or warm start will not be enough to finalize the reset. Try the operation again, making sure to power off and on the device within the time limit.
Once you have fixed the password issue and regained access, implement these steps to ensure it never happens again:
Power off the PLC, insert the card, and power it back on. The CPU will reset to defaults, removing the password. Wipeout Utility : Siemens provides a standalone Wipeout.exe
When you upload the unlocked program, immediately go to File > Export > Source Code . Save it as an encrypted .awl or .s7p file on a network drive, not just a local PC.
To mitigate the operational risks of forgotten passwords, automation departments should implement rigorous configuration control protocols:
Password required for both uploading and downloading.
"Not for a restore," she whispered, her eyes bright. "There’s a trick with the firmware. If we can trigger a system-level wipe while the 'read-only' attribute is toggled in the memory map, sometimes the CPU dumps the hash into the buffer before it clears."
Some integrators wire a small DIP switch to the CPU’s RUN/TERM/STOP keys or to the SD card detect pin. Flipping the switch before power-up triggers a custom bootloader that disables password checking. This is a hardware-level fixed unlock for future needs.
To ensure you never have to resort to risky unlocking methods in the future, implement robust data and project management protocols: