System32 has disappeared

Hi Guys For some unknown reason my System32 has completely disappeard from my Windows Folder. I don't have any viruses that I am aware of as I ran Nod32 and it didn't pick up any but it does read my System32 folder. So it must be there, I just can't see it. Can windows turn it on and off automatically?? Oh, I did have a problem with my Regedit and Taskmanager in that I couldn't access them but Nod32 said I had the Win32.P2P-Worm.Alcan.A virus but it has been cleaned, and I can now access my Taskbar and Regedit in CMD. But my System32 folder has disappeared?? Thanks for your help

In any explorer type window, click on tools, choose folder options. Under the "view" tab check "show hid files and folders"