Booting into Windows RE
Configure the boot order in the BIOS such that the first boot device is your CD/DVD drive.
Insert the Windows 7/Vista Setup DVD and restart the computer.
Alternately, you may use the Windows 7/Vista System Repair Disc if you have one.
When prompted, press a key to boot from the DVD. In the "Install Windows" screen, click Repair your computer
Select your Windows installation, and click Next
Editor’s Note: Make a note of the drive-letter of your Windows 7 installation, as seen from Windows RE.
This is the drive-letter you want to reference when running Sfc.exe offline.
Click Command Prompt
To scan the integrity (and repair) a specific file, use this command:
sfc /scanfile=d:\windows\system32\zipfldr.dll /offbootdir=d:\ /offwindir=d:\windows
The above command scans the file zipfldr.dll and replaces it if required.
To scan the integrity of all system files and repair them, run this command:
sfc /scannow /offbootdir=d:\ /offwindir=d:\windows
This process takes some time (<5 min) to complete, and there weren’t any integrity violations.