Salve
da qualche giorno , durante la navigazione il modem si disconnette da solo, piu' volte fino a non riconnettersi piu.
Credo di essere stato infettato...mi controllereste il log per cortesia.
Grazie Fab

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 17.33.48, on 08/09/2009
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
Boot mode: Normal

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\nvsvc32.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\ATKKBService.exe
C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\File comuni\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\WINDOWS\System32\svchost.exe
C:\Programmi\nHancer\nHancerService.exe
C:\WINDOWS\System32\svchost.exe
C:\Programmi\CyberLink\Shared files\RichVideo.exe
C:\WINDOWS\System32\PAStiSvc.exe
C:\WINDOWS\system32\svchost.exe
C:\PROGRA~1\AVG\AVG8\avgemc.exe
C:\PROGRA~1\AVG\AVG8\avgrsx.exe
C:\PROGRA~1\AVG\AVG8\avgnsx.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\AVG\AVG8\avgcsrvx.exe
C:\Programmi\Analog Devices\Core\smax4pnp.exe
C:\Programmi\Analog Devices\SoundMAX\Smax4.exe
C:\Programmi\Saitek\SD6\Software\ProfilerU.exe
C:\Programmi\Saitek\SD6\Software\SaiMfd.exe
C:\WINDOWS\system32\GSICON.EXE
C:\WINDOWS\system32\dslagent.exe
C:\Programmi\HP\HP Software Update\HPWuSchd2.exe
C:\PROGRA~1\AVG\AVG8\avgtray.exe
C:\WINDOWS\system32\RUNDLL32.EXE
C:\Programmi\File comuni\Ahead\Lib\NMBgMonitor.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Messenger\msmsgs.exe
C:\Programmi\HP\Digital Imaging\bin\hpqtra08.exe
C:\Programmi\MagicDisc\MagicDisc.exe
C:\Programmi\File comuni\Ahead\Lib\NMIndexStoreSvr.exe
C:\Programmi\HP\Digital Imaging\bin\hpqSTE08.exe
C:\Programmi\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.libero.it/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: btorbit.com - {000123B4-9B42-4900-B3F7-F4B073EFC214} - C:\Programmi\Orbitdownloader\orbitcth.dll
O2 - BHO: HP Print Enhancer - {0347C33E-8762-4905-BF09-768834316C61} - C:\Programmi\HP\Smart Web Printing\hpswp_printenhancer.dll
O2 - BHO: HP Print Clips - {053F9267-DC04-4294-A72C-58F732D338C0} - C:\Programmi\HP\Smart Web Printing\hpswp_framework.dll
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Programmi\File comuni\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Programmi\AVG\AVG8\avgssie.dll
O2 - BHO: Megaupload Toolbar - {4E7BD74F-2B8D-469E-CCB0-B130EEDBE97C} - C:\Programmi\MegauploadToolbar\megauploadtoolbar.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_03\bin\ssv.dll
O2 - BHO: Guida per l'accesso a Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Programmi\Google\GoogleToolbarNotifier\5.1.1309.3572\swg.dll
O2 - BHO: MegaIEMn - {bf00e119-21a3-4fd1-b178-3b8537e75c92} - C:\Programmi\Megaupload\Mega Manager\MegaIEMn.dll
O3 - Toolbar: &WebTrad - {7056E733-8C57-4E4E-9085-E50DE6F3374E} - C:\Programmi\Expert System\PlanetGate\IEETRADBANDS.DLL
O3 - Toolbar: Megaupload Toolbar - {4E7BD74F-2B8D-469E-CCB0-B130EEDBE97C} - C:\Programmi\MegauploadToolbar\megauploadtoolbar.dll
O3 - Toolbar: Grab Pro - {C55BBCD6-41AD-48AD-9953-3609C48EACC7} - C:\Programmi\Orbitdownloader\GrabPro.dll
O4 - HKLM\..\Run: [SoundMAXPnP] "C:\Programmi\Analog Devices\Core\smax4pnp.exe"
O4 - HKLM\..\Run: [SoundMAX] "C:\Programmi\Analog Devices\SoundMAX\Smax4.exe" /tray
O4 - HKLM\..\Run: [LanguageShortcut] C:\Programmi\CyberLink\PowerDVD\Language\Language.exe
O4 - HKLM\..\Run: [ProfilerU] C:\Programmi\Saitek\SD6\Software\ProfilerU.exe
O4 - HKLM\..\Run: [SaiMfd] C:\Programmi\Saitek\SD6\Software\SaiMfd.exe
O4 - HKLM\..\Run: [GSICONEXE] GSICON.EXE
O4 - HKLM\..\Run: [DSLAGENTEXE] dslagent.exe USB
O4 - HKLM\..\Run: [HP Software Update] C:\Programmi\HP\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [AVG8_TRAY] C:\PROGRA~1\AVG\AVG8\avgtray.exe
O4 - HKLM\..\Run: [nwiz] C:\Programmi\NVIDIA Corporation\nView\nwiz.exe /install
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKCU\..\Run: [BgMonitor_{79662E04-7C6C-4d9f-84C7-88D8A56B10AA}] "C:\Programmi\File comuni\Ahead\Lib\NMBgMonitor.exe"
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [MSMSGS] "C:\Programmi\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [swg] C:\Programmi\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - Startup: MagicDisc.lnk = C:\Programmi\MagicDisc\MagicDisc.exe
O4 - Global Startup: HP Digital Imaging Monitor.lnk = C:\Programmi\HP\Digital Imaging\bin\hpqtra08.exe
O8 - Extra context menu item: &Download by Orbit - res://C:\Programmi\Orbitdownloader\orbitmxt.dll/201
O8 - Extra context menu item: &Grab video by Orbit - res://C:\Programmi\Orbitdownloader\orbitmxt.dll/204
O8 - Extra context menu item: &Point&&Go - C:\Programmi\File comuni\Expert System\PGPlatform\PGPlatform.htm
O8 - Extra context menu item: Do&wnload selected by Orbit - res://C:\Programmi\Orbitdownloader\orbitmxt.dll/203
O8 - Extra context menu item: Down&load all by Orbit - res://C:\Programmi\Orbitdownloader\orbitmxt.dll/202
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O8 - Extra context menu item: Scarica con Download &Express - C:\Programmi\Download Express\Add_Url.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: Libro dei ritagli HP - {58ECB495-38F0-49cb-A538-10282ABF65E7} - C:\Programmi\HP\Smart Web Printing\hpswp_extensions.dll
O9 - Extra button: Selezione intelligente HP - {700259D7-1666-479a-93B1-3250410481E8} - C:\Programmi\HP\Smart Web Printing\hpswp_extensions.dll
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
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: {1E54D648-B804-468d-BC78-4AFFED8E262E} (System Requirements Lab) - http://www.nvidia.com/content/DriverDownload/srl/3.0.0.0/srl_bin/sysreqlab3.cab
O16 - DPF: {67A5F8DC-1A4B-4D66-9F24-A704AD929EEE} (System Requirements Lab) - http://www.nvidia.com/content/DriverDownload/srl/2.0.0.1/sysreqlab2.cab
O16 - DPF: {CE69F98F-2AF3-4306-BAC6-A79070EDA1B4} - http://eu.download.games.yahoo.com/zylom/activex/zylomloader.cab
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Programmi\AVG\AVG8\avgpp.dll
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FILECO~1\Skype\SKYPE4~1.DLL
O20 - Winlogon Notify: avgrsstarter - C:\WINDOWS\SYSTEM32\avgrsstx.dll
O23 - Service: ATK Keyboard Service (ATKKeyboardService) - ASUSTeK COMPUTER INC. - C:\WINDOWS\ATKKBService.exe
O23 - Service: AVG Free8 E-mail Scanner (avg8emc) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgemc.exe
O23 - Service: AVG Free8 WatchDog (avg8wd) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
O23 - Service: Google Update Service (gupdate) (gupdate) - Google Inc. - C:\Programmi\Google\Update\GoogleUpdate.exe
O23 - Service: Google Software Updater (gusvc) - Google - C:\Programmi\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Programmi\File comuni\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: NBService - Nero AG - C:\Programmi\Nero\Nero 7\Nero BackItUp\NBService.exe
O23 - Service: nHancer Support (nHancer) - KSE - Korndörfer Software Engineering - C:\Programmi\nHancer\nHancerService.exe
O23 - Service: NVIDIA Display Driver Service (nvsvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Cyberlink RichVideo Service(CRVS) (RichVideo) - Unknown owner - C:\Programmi\CyberLink\Shared files\RichVideo.exe
O23 - Service: PC Tools Auxiliary Service (sdAuxService) - PC Tools - C:\Programmi\Spyware Doctor\pctsAuxs.exe
O23 - Service: PC Tools Security Service (sdCoreService) - PC Tools - C:\Programmi\Spyware Doctor\pctsSvc.exe
O23 - Service: STI Simulator - Unknown owner - C:\WINDOWS\System32\PAStiSvc.exe

--
End of file - 10139 bytes

Il log non sembra messo male.
Elimina queste voci di HJT:
O2 - BHO: Megaupload Toolbar - {4E7BD74F-2B8D-469E-CCB0-B130EEDBE97C} - C:\Programmi\MegauploadToolbar\megauploadtoolbar.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_03\bin\ssv.dll
O4 - HKCU\..\Run: [MSMSGS] "C:\Programmi\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [swg] C:\Programmi\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
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
O16 - DPF: {1E54D648-B804-468d-BC78-4AFFED8E262E} (System Requirements Lab) - http://www.nvidia.com/content/DriverDownload/srl/3.0.0.0/srl_bin/sysreqlab3.cab
O16 - DPF: {67A5F8DC-1A4B-4D66-9F24-A704AD929EEE} (System Requirements Lab) - http://www.nvidia.com/content/DriverDownload/srl/2.0.0.1/sysreqlab2.cab
O16 - DPF: {CE69F98F-2AF3-4306-BAC6-A79070EDA1B4} - http://eu.download.games.yahoo.com/zylom/activex/zylomloader.cab

Vai in Installazione Applicazioni, e rimuovi tutte le Toolbar che trovi, e tutte le versioni Java che trovi.
Dai una pulita (registro compreso)con CCleaner http://www.aiutaamici.com/software?ID=11223
Nella schermata iniziale di CCleaner, clicca su Opzioni e poi Avanzate, togli il segno di spunta a: Cancella i file in Windows Temp solo se più vecchi di 48 ore. (poi esegui le pulizie)

Scarica ed installa MalwareBytes:
clicca qui per il download : http://www.aiutamici.com/software?id=80346
Prima di fare la scansione AGGIORNALO. (è molto importante)
Esegui una scansione completa del sistema.
Posta il log.

Perchè indipendentemente dalla connessione, essendo fortemente obsolete, sono soggette a vulnerabilità enormi.
Il Java, è uno dei bersagli preferiti, degli Hacker, proprio perchè sanno che l'utente, non sempre lo tiene aggiornato, e sfruttano le falle, delle versioni vecchie, che trovano installate.
Naturalmente, dopo che ho visto il log di MBAM, gli farò installare l'ultima versione.

Figurati......

Elimina quello che ha trovato Malwarebytes.

Vai in Installazione Applicazioni, e rimuovi tutte le versioni Java che trovi.
Pulisci con CCleaner, e Riavvia il pc.
Installa l'ultima versione:
http://www.java.com/it/download/index.jsp

Prima di farti fare altre scansioni, dovresti fare una prova, riguardo le continue disconnessioni:
Disistallare il Firewall. (per un periodo )
In molti casi è lui il colpevole.