If you are trying to open the file and it is locked, the most common password for such educational or "puzzle" archives is often nandc , password , or 1234 .
If you are running a program and it says a "piece" is missing from this archive, it usually refers to a specific library file (like a .dll ) or a configuration file (like config.ini ) that failed to extract properly.
The "piece" you are looking for depends on your current task:
If this is for a coding assignment, the "piece" refers to the symbols 'X' and 'O' .