I am surprise that no one told him to run sfc in dos. System File checker- viruses and adware can delete dos commands trying to make it harder for you to delete them. also some uninstallers not written well can delete more than their software.
Microsoft Windows XP Syntax
SFC [/SCANNOW] [/SCANONCE] [/SCANBOOT] [/REVERT] [/PURGECACHE] [/CACHESIZE=x]
/SCANNOWScans all protected system files immediately./SCANONCEScans all protected system files once at the next boot./SCANBOOTScans all protected system files at every boot./REVERTReturn scan to default setting./PURGECACHEPurges the file cache./CACHESIZE=xSets the file cache size.
/SCANNOW Scans all protected system files immediately.
/SCANONCE Scans all protected system files once at the next boot.
/SCANBOOT Scans all protected system files at every boot.
/REVERT Return scan to default setting.
/PURGECACHE Purges the file cache.
/CACHESIZE=x Sets the file cache size.
best and free solution to stop this from happening is superantispyware, and MS security essentails.
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