Minecraft region files corrupted

Solution 1:

I looked at the files and most of them are either corrupted or have been modified in some way. While most of the files are from 2014, there are 3 files from 2017 in the archive that are not corrupted. Unfortunately, they contain pristine terrain without any structures. One of these 3 files is from region 1.1 where the coordinates 600, 600 are. There are no buildings there. It is possible that the chunks were regenerated by the chunk fixer you mentioned. Either way, there is no way to restore buildings in that region. Do you happen to have the original files before the use of chunk fixer?