Microsoft Windows Resource Checker (SFC.exe) refers to a component of Vista that can help you troubleshoot crashes that occur in the user mode part of Windows Vista. These crashes may be related to missing or damaged operating system files.
The SFC.exe program performs the following operations:
? It verifies that non-configurable Windows Vista system files have not changed. Also, it verifies that these files match the operating system's definition of which files are expected to be installed on the computer.
? It repairs non-configurable Windows Vista system files, when it is possible.
For more information check out
How to analyze the log file entries that the Microsoft Windows Resource Checker (SFC.exe) program generates in Windows Vista
Steve