Corrupt files in project

Hello,
I need help to fix problem with corrupt files in project. My project crash when I open it and says corrupt file in project.

How do I fix it?
link text

If this map has become corrupt, likely due to the crash occurring while the file was being saved, you may be able to load a Backup of the map from your Backup folder which can be found in the project’s directory under Saved/Backup. Otherwise, you’ll need to recreate the map. In the future, please make backups often and consider using Source Control to avoid losing your files.