deifobe, grazie mille
il pc sembra essere perfettamente pulito adesso, comunque ti posto il log di hijackthis (io non vi ho trovato nulla di anomalo)
Logfile of HijackThis v1.99.1
Scan saved at 19.14.33, on 14/11/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\Alwil Software\Avast4\aswUpdSv.exe
C:\Programmi\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\system32\spoolsv.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Programmi\Java\jre1.6.0_03\bin\jusched.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Spybot - Search & Destroy\TeaTimer.exe
C:\Programmi\SUPERAntiSpyware\SUPERAntiSpyware.exe
C:\Programmi\Alwil Software\Avast4\ashMaiSv.exe
C:\Programmi\Alwil Software\Avast4\ashWebSv.exe
C:\WINDOWS\system32\wscntfy.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Programmi\Hijackthis\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.it/
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Int ernet Settings,ProxyOverride = 127.0.0.1
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O3 - Toolbar: Windows Live Toolbar - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Programmi\Windows Live Toolbar\msntb.dll
O4 - HKLM\..\Run: [NeroCheck] C:\WINDOWS\system32\\NeroCheck.exe
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\Java\jre1.6.0_03\bin\jusched.exe "
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Programmi\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKCU\..\Run: [SUPERAntiSpyware] C:\Programmi\SUPERAntiSpyware\SUPERAntiSpyware.exe
O8 - Extra context menu item: &Windows Live Search - res://C:\Programmi\Windows Live Toolbar\msntb.dll/search.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_03\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_03\bin\ssv.dll
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O16 - DPF: {0EB0E74A-2A76-4AB3-A7FB-9BD8C29F7F75} (CKAVWebScan Object) - http://www.kaspersky.com/kos/eng/par...an_unicode.cab
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O20 - AppInit_DLLs: C:\WINDOWS\system32\__c0083AE4.dat
O20 - Winlogon Notify: !SASWinLogon - C:\Programmi\SUPERAntiSpyware\SASWINLO.dll
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Programmi\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Programmi\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - Unknown owner - C:\Programmi\Alwil Software\Avast4\ashMaiSv.exe" /service (file missing)
O23 - Service: avast! Web Scanner - Unknown owner - C:\Programmi\Alwil Software\Avast4\ashWebSv.exe" /service (file missing)
mi sono accorto solo ora dei due (file missing) finali... è colpa del virus o del fatto che avevo temporaneamente disabilitato avast?