In Windows system, Sfc.exe (system file checker) is used to validate system file integration and repair system files. In Windows XP, the function is more powerful: we can use the tool to realize recovery function, the “System file checker” in Windows XP could scan all protected system files to validate their versions, which could also set up file cache size, clear file cache and refill the folder “”%SystemRoot%＼System32＼Dllcache
 To enable “System file checker” in Windows XP, first run “Command prompt”: click “Start”—“All programs”—“Accessories”—“Command prompt”, or just click “Start”—“Run” command, and keyed “cmd” to the command line and press Enter key. Afterwards, on “Command prompt” windows, keyed “Sfc” behind the cursor prompt, and press Enter key.
  For instance, we keyed “Sfc/SCANNOW”, press Enter key and then “System file checker” will start checking current system files, whether there’s damage, or whether the version is correct. Application will ask you to insert Windows XP installation disc to repair or to replace the incorrect files. If Dllcache folder is broken or unavailable, you can still use “Sfc/scanonce” or “Sfc/scanboot” command to repair the content of this folder to ensure the security and stability of