- Check Trash Bin:
Check your trash/recycle bin for deleted files, and undelete them by selecting the file and pressing the Restore button on the side. - Check Backups:
If you have a backup, such as one made with Time Machine on a Mac or File History on Windows, use it to restore your deleted files. - Data Recovery Software:
Use third-party data recovery software, such as Rescue Data, to check your hard drive for hidden, or lost files.