RPG MAKER VX UNEXPECTED FILE FORMAT

This is probably a loss of data problem: RPG Makers don't believe in proper file saving techniques to prevent this kind of problem during issues when saving. Make a new project and copy your game project data files into the new project one by one and try opening the project. Save the maps for last. If a file causes the "Unexpected File Format" error, it's pretty much history. Use a backup or a copy of the game (if available) and copy the data file from that into the project. Otherwise the file is lost and can't be replaced.