Infecté Win32:Vundo@dll et Win32:Trojan-gen

Bonjour, je viens d'analyser mon ordinateur suite à de nombreuses alertes par avast.

Que faire pour me débarrasser de tout ça?

Voici l'historique des alertes de la journée:
27/05/2008 12:51:04 1211885464 ALIX 296 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\awtttSmn.dll" file.
27/05/2008 13:51:05 1211889065 ALIX 296 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\opnmLbYp.dll" file.
27/05/2008 14:16:56 1211890616 ALIX 836 Sign of "Win32:Trojan-gen {Other}" has been found in "C:\Documents and Settings\ALIX\Local Settings\Temp\snapsnet.exe" file.
27/05/2008 14:18:11 1211890691 ALIX 836 Sign of "Win32:Trojan-gen {UPX}" has been found in "C:\Documents and Settings\ALIX\Local Settings\Temp\winvsnet.exe" file.
27/05/2008 14:51:05 1211892665 ALIX 296 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\iiffFvtr.dll" file.
27/05/2008 15:41:58 1211895718 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\byXNhhHY.dll" file.
27/05/2008 15:51:04 1211896264 ALIX 296 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\khfDwuVP.dll" file.
27/05/2008 16:46:12 1211899572 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\byXOiIXR.dll" file.
27/05/2008 16:47:25 1211899645 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\fccddeeb.dll" file.
27/05/2008 16:47:32 1211899652 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\hgGawTNG.dll" file.
27/05/2008 16:47:34 1211899654 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\hgGwVLBU.dll" file.
27/05/2008 16:47:46 1211899666 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\jkkiFvWO.dll" file.
27/05/2008 16:48:16 1211899696 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\nnnkLDwX.dll" file.
27/05/2008 16:48:21 1211899701 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\nnnljIYR.dll" file.
27/05/2008 16:49:24 1211899764 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\ssqQgHwX.dll" file.
27/05/2008 16:50:02 1211899802 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\wvUOGYrq.dll" file.
27/05/2008 16:50:14 1211899814 ALIX 836 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\xxyyvvvS.dll" file.
27/05/2008 16:51:09 1211899869 ALIX 296 Sign of "Win32:Vundo@dll [Trj]" has been found in "C:\WINDOWS\system32\cbXRIyxY.dll" file.

Merci d'avance