The latest patch for PES 2012 is currently unavailable for Xbox 360 users in some parts of Latin America. Players from countries including Brazil, Argentina, Chile and Uruguay are all reporting the problem.
Apparently, the issue has been caused by the new 1.02 update.
Not for the first time, the problem seems to be only affecting those on Xbox 360. There appears to be no issues on the PC and PS3.
Konami have stated that they are working with Microsoft, trying to find a solution, but have also admitted that they do not know when the situation will be fixed.