Ho fatto come mi hai detto ma dopo due giorni ci risiamo con altri problemi.
Vi rimando il nuovo log.
Grazie come sempre.

Logfile of HijackThis v1.98.2
Scan saved at 10.32.05, on 03/08/2005
Platform: Windows 2000 SP4 (WinNT 5.00.2195)
MSIE: Internet Explorer v6.00 SP1 (6.00.2800.1106)

Running processes:
C:\WINNT\System32\smss.exe
C:\WINNT\system32\winlogon.exe
C:\WINNT\system32\services.exe
C:\WINNT\system32\lsass.exe
C:\WINNT\system32\svchost.exe
C:\WINNT\system32\spoolsv.exe
C:\Programmi\NavNT\defwatch.exe
C:\WINNT\System32\svchost.exe
C:\Programmi\NavNT\rtvscan.exe
C:\WINNT\system32\regsvc.exe
C:\WINNT\system32\MSTask.exe
C:\WINNT\System32\WBEM\WinMgmt.exe
C:\WINNT\system32\svchost.exe
C:\WINNT\Explorer.EXE
C:\WINNT\system32\ievs32.exe
C:\WINNT\system32\atiptaxx.exe
C:\Programmi\NavNT\vptray.exe
C:\WINNT\system32\spool\drivers\w32x86\3\hpztsb09.exe
C:\Programmi\HP\hpcoretech\hpcmpmgr.exe
C:\Programmi\Hewlett-Packard\HP Software Update\HPWuSchd2.exe
C:\Programmi\Hewlett-Packard\Digital Imaging\bin\hpotdd01.exe
C:\WINNT\system32\atlen32.exe
C:\Programmi\WinZip\WZQKPICK.EXE
C:\WINNT\system32\wuauclt.exe
C:\Documents and Settings\mpilustri\Desktop\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = res://C:\WINNT\pljhr.dll/sp.html#63796
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = res://C:\WINNT\pljhr.dll/sp.html#63796
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.it/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = about:blank
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = res://C:\WINNT\pljhr.dll/sp.html#63796
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Bar = res://C:\WINNT\pljhr.dll/sp.html#63796
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = res://C:\WINNT\pljhr.dll/sp.html#63796
R1 - HKCU\Software\Microsoft\Internet Explorer\Search,SearchAssistant = res://C:\WINNT\pljhr.dll/sp.html#63796
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant = res://C:\WINNT\pljhr.dll/sp.html#63796
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
R3 - Default URLSearchHook is missing
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\Adobe\Acrobat 6.0\Reader\ActiveX\AcroIEHelper.dll
O2 - BHO: Class - {C66D29D3-21B7-FF47-CAF3-8F83E9ADC959} - C:\WINNT\system32\sdknx.dll
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINNT\System32\msdxm.ocx
O4 - HKLM\..\Run: [Synchronization Manager] mobsync.exe /logon
O4 - HKLM\..\Run: [AtiPTA] atiptaxx.exe
O4 - HKLM\..\Run: [vptray] C:\Programmi\NavNT\vptray.exe
O4 - HKLM\..\Run: [HPDJ Taskbar Utility] C:\WINNT\system32\spool\drivers\w32x86\3\hpztsb09.exe
O4 - HKLM\..\Run: [HP Component Manager] "C:\Programmi\HP\hpcoretech\hpcmpmgr.exe"
O4 - HKLM\..\Run: [HP Software Update] "C:\Programmi\Hewlett-Packard\HP Software Update\HPWuSchd2.exe"
O4 - HKLM\..\Run: [DeviceDiscovery] C:\Programmi\Hewlett-Packard\Digital Imaging\bin\hpotdd01.exe
O4 - HKLM\..\Run: [d3bd32.exe] C:\WINNT\d3bd32.exe
O4 - HKLM\..\Run: [ipoh32.exe] C:\WINNT\system32\ipoh32.exe
O4 - HKLM\..\Run: [ietk.exe] C:\WINNT\ietk.exe
O4 - HKLM\..\Run: [sdkrr.exe] C:\WINNT\sdkrr.exe
O4 - HKLM\..\Run: [netfq.exe] C:\WINNT\system32\netfq.exe
O4 - HKLM\..\Run: [sdkyi32.exe] C:\WINNT\sdkyi32.exe
O4 - HKLM\..\Run: [atlen32.exe] C:\WINNT\system32\atlen32.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Programmi\Microsoft Office\Office\OSA9.EXE
O4 - Global Startup: WinZip Quick Pick.lnk = C:\Programmi\WinZip\WZQKPICK.EXE
O9 - Extra button: Microsoft® JavaScript® Console - {A3E1E022-5625-4A9F-AC60-F4DB4B541283} - C:\WINNT\system32\Comdlg32.ocx
O9 - Extra 'Tools' menuitem: JavaScript Console - {A3E1E022-5625-4A9F-AC60-F4DB4B541283} - C:\WINNT\system32\Comdlg32.ocx
O9 - Extra button: Microsoft® JavaScript® Console - {A3E1E022-5625-4A9F-AC60-F4DB4B541283} - C:\WINNT\system32\Comdlg32.ocx (HKCU)
O9 - Extra 'Tools' menuitem: JavaScript Console - {A3E1E022-5625-4A9F-AC60-F4DB4B541283} - C:\WINNT\system32\Comdlg32.ocx (HKCU)
O17 - HKLM\System\CCS\Services\Tcpip\..\{2D85FB0E-FD8C-4ECF-8940-E6A65D2FB0C0}: NameServer = 212.131.30.42,212.131.30.43
O17 - HKLM\System\CS1\Services\Tcpip\Parameters: SearchList = interbusiness.it
O17 - HKLM\System\CS1\Services\Tcpip\..\{2D85FB0E-FD8C-4ECF-8940-E6A65D2FB0C0}: NameServer = 212.131.30.42,212.131.30.43
O17 - HKLM\System\CS2\Services\Tcpip\Parameters: SearchList = interbusiness.it
O17 - HKLM\System\CS2\Services\Tcpip\..\{2D85FB0E-FD8C-4ECF-8940-E6A65D2FB0C0}: NameServer = 212.131.30.42,212.131.30.43
O17 - HKLM\System\CCS\Services\Tcpip\Parameters: SearchList = interbusiness.it
O18 - Protocol: cetihpz - {CF184AD3-CDCB-4168-A3F7-8E447D129300} - C:\Programmi\HP\hpcoretech\comp\hpuiprot.dll