Win32: trojan-gen (other)

Bonjour à toutes et tous

Bon je vais rester calme mais cette machine me rend dingue.

Je n'arrive pas à me defaire d'une floppée de trojan :
- win32:trojan-gen(other)
- JS:Istbar
- win32:LOWZONES-M

Voila je ne sais lus quoi faire. Après Avast, ad-aware, spybot.
Un scan en ligne dont voici le compte rendu

Scan started at 02/05/2005 12:41:46

Scanning memory...
Scanning boot sectors...
Scanning files...
C:\oi.exe->(UPXW)->(RARSfx)->kansy.reg - Trojan:BAT/LowZones.O* -> Infected
C:\oi.exe->(UPXW)->(RARSfx)->kany.reg - Trojan:BAT/LowZones.N* -> Infected
C:\oi.exe->(RARSfx)->kansy.reg - Trojan:BAT/LowZones.O* -> Infected
C:\oi.exe->(RARSfx)->kany.reg - Trojan:BAT/LowZones.N* -> Infected
C:\Documents and Settings\Thierry\Local Settings\Temporary Internet Files\Content.IE5\S5U1W6MZ\io[1].exe->(UPXW)->(RARSfx)->kansy.reg - Trojan:BAT/LowZones.O* -> Infected
C:\Documents and Settings\Thierry\Local Settings\Temporary Internet Files\Content.IE5\S5U1W6MZ\io[1].exe->(UPXW)->(RARSfx)->kany.reg - Trojan:BAT/LowZones.N* -> Infected
C:\Documents and Settings\Thierry\Local Settings\Temporary Internet Files\Content.IE5\S5U1W6MZ\io[1].exe->(RARSfx)->kansy.reg - Trojan:BAT/LowZones.O* -> Infected
C:\Documents and Settings\Thierry\Local Settings\Temporary Internet Files\Content.IE5\S5U1W6MZ\io[1].exe->(RARSfx)->kany.reg - Trojan:BAT/LowZones.N* -> Infected
C:\WINDOWS\kansy.reg - Trojan:BAT/LowZones.O* -> Infected
C:\WINDOWS\kany.reg - Trojan:BAT/LowZones.N* -> Infected
C:\WINDOWS\system32\SCardClnt.exe - Backdoor:Win32/Rbot.KS -> Infected

Scanned
============================
Objects: 17541
Directories: 1568
Archives: 585
Size(Kb): -910869
Infected files: 11

Found
============================
Viruses found: 3
Suspicious files: 0
Disinfected files: 0
Mail files: 53
Si vous pouvez m'aider merci