The below step will show you show you how to show hidden files and folders and system-protected files / folders in windows 7.
Show hidden files and folders in Windows 7
2. Click the View Tab,under Advanced settings, click Show hidden files, folders, and drives, and then click OK.
To Show Protected Operating System Files in Windows 7
The same way as show hidden files and folders ,in the folder options window,clear the check-box of hide protected operating system files .