Voila...il est dans mon fichier windows Svchost.exe j´ai telechargé fix welchia de symatec il a fini il me dit :
The service " WksPatch" is viral. It is deleted.
The process " svchost.exe" is viral. It is terminated.
W32.Welchia.Worm has been successfully removed
from your computer!
Here is the report:
The total number of the scanned files: 38093
The number of deleted files: 0
The number of repaired files: 0
The number of viral processes terminated: 1
The number of viral services deleted: 1
The number of registry entries fixed: 0
Mdr je redemare le pc et...Il est toujours la
je fais CTRL ALT SUPR, processus actifs, je fé supprimer SVCHOST.exe et la , compte a rebours ARRRG 
Autrement j´ai bien desactivé la restauration du systeme comme indiqué.
Si vous pouvez m´aider merci ! @++