Restore from a known good image

The specific workings can vary depending on the software, but generally, the process involves:

Connect the PLC to your PC using the appropriate communication cable. Navigate to the "Communication" or "PLC" menu and select "Format PLC Memory" or a similar clear command.

If you are locked out of a Delta PLC, you should always exhaust official, safe routes before considering drastic measures. Step 1: Check Factory Default Configurations

While these tools offer a quick fix, downloading unverified software poses severe risks:

: Restricts viewing of the ladder logic within the software.

Never use unlock software on a machine still under OEM contract. You may unlock it, but you also unlock the OEM’s right to deny support.

Store all industrial automation passwords in secure enterprise managers like Keepass, 1Password, or Bitwarden, accessible only to authorized maintenance staff.

Restricts viewing/editing the program code.

Some "new" software patches or manipulates the system memories (registers) where password data is temporarily loaded during authorization.