You might assume that there is no chance of recovering the original; you might be able to save a copy of the overwritten file by using the Volume Shadow Copy tools in your OS.
Instructions
• Click on the "Start" menu and choose "Search."
• Select the option to search for "All Files and Folders."
• Type in the name of the overwritten file and press the "Search" button.
• Right-click on the file and choose the "Properties" option.
• Choose the "Previous Versions" tab and choose the version of the file which you want to restore from the menu onscreen.
• Click on the "Restore" button.