You need a clean ISO of Winning Eleven 2012 or Winning Eleven 2014 (depending on which modding group released the "I" version). The "I" series typically patches the Japanese version for stability.

Look for "I Winning Eleven 2015 Final Patch" on forums like PES-Patch.com , Evo-Web , or archive.org. The file is usually a .ppf or .xdelta patch file. The best version is the "Season Finale" edition released in July 2015.

It is better because it respects your time. It is better because it rewards football intelligence over credit card swipes. It is better because the community kept the flame alive.