Avira Antivirus segnala:

Nel file 'C:\WINDOWS\gckhp.exe'
è stato rilevato un virus o programma indesiderato 'TR/Drop.Injector.ycd' [trojan].
Azione eseguita: Nega accesso

non riesco a toglierlo e mi blocca Microsoft Word non facendomi salvare i file.

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 0.29.33, on 07/12/2011
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.17103)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\csrss.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\System32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\Avira\AntiVir Desktop\sched.exe
C:\WINDOWS\anvshell.exe
C:\WINDOWS\SOUNDMAN.EXE
C:\Programmi\Avira\AntiVir Desktop\avgnt.exe
C:\Programmi\HP\HP Software Update\HPWuSchd2.exe
C:\WINDOWS\system32\rundll32.exe
C:\Programmi\SweetIM\Messenger\SweetIM.exe
C:\Programmi\Microsoft Office\Office12\GrooveMonitor.exe
C:\PROGRA~1\IMESHA~1\MediaBar\Datamngr\DATAMN~1.EXE
C:\Programmi\Malwarebytes' Anti-Malware\mbamgui.exe
C:\Programmi\uTorrent\uTorrent.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\HP\Digital Imaging\bin\hpqtra08.exe
C:\Programmi\Avira\AntiVir Desktop\avguard.exe
C:\WINDOWS\asuskbservice.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\Malwarebytes' Anti-Malware\mbamservice.exe
C:\Programmi\CDBurnerXP\NMSAccessU.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\Programmi\Avira\AntiVir Desktop\avshadow.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\HP\Digital Imaging\bin\hpqSTE08.exe
C:\WINDOWS\System32\alg.exe
C:\Programmi\Mozilla Firefox\firefox.exe
C:\Programmi\Mozilla Firefox\plugin-container.exe
C:\Documents and Settings\pinotto\Documenti\Download\HiJackThis.exe
C:\WINDOWS\system32\wbem\wmiprvse.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://downloads.phpnuke.org/it/index.php?rvs=hompag
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.google.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://downloads.phpnuke.org/it/index.php?rvs=hompag
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://downloads.phpnuke.org/it/index.php?rvs=hompag
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant = http://search.babylon.com/?babsrc=SP_ss&q={searchTerms}&mntrId=f0bd43e9000000000000000e2e9715ad&tlver=1.4.19.19&ss=1&affID=17982
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
R3 - URLSearchHook: PHPNukeIT Toolbar - {2c965f3f-8efd-4bfc-a2c5-1672845fdbbf} - C:\Programmi\PHPNukeIT\prxtbPHPN.dll
O2 - BHO: MediaBar - {28387537-e3f9-4ed7-860c-11e69af4a8a0} - C:\PROGRA~1\IMESHA~1\MediaBar\ToolBar\imeshdtxmltbpi.dll
O2 - BHO: PHPNukeIT - {2c965f3f-8efd-4bfc-a2c5-1672845fdbbf} - C:\Programmi\PHPNukeIT\prxtbPHPN.dll
O2 - BHO: UrlHelper Class - {474597C5-AB09-49d6-A4D5-2E8D7341384E} - C:\PROGRA~1\IMESHA~1\MediaBar\Datamngr\IEBHO.dll
O2 - BHO: Groove GFS Browser Helper - {72853161-30C5-4D22-B7F9-0BBC1D38A37E} - C:\Programmi\Microsoft Office\Office12\GrooveShellExtensions.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_06\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O3 - Toolbar: PHPNukeIT Toolbar - {2c965f3f-8efd-4bfc-a2c5-1672845fdbbf} - C:\Programmi\PHPNukeIT\prxtbPHPN.dll
O3 - Toolbar: MediaBar - {28387537-e3f9-4ed7-860c-11e69af4a8a0} - C:\PROGRA~1\IMESHA~1\MediaBar\ToolBar\imeshdtxmltbpi.dll
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [anvshell] anvshell.exe
O4 - HKLM\..\Run: [SoundMan] SOUNDMAN.EXE
O4 - HKLM\..\Run: [avgnt] "C:\Programmi\Avira\AntiVir Desktop\avgnt.exe" /min
O4 - HKLM\..\Run: [HP Software Update] C:\Programmi\HP\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [BluetoothAuthenticationAgent] rundll32.exe bthprops.cpl,,BluetoothAuthenticationAgent
O4 - HKLM\..\Run: [SweetIM] C:\Programmi\SweetIM\Messenger\SweetIM.exe
O4 - HKLM\..\Run: [GrooveMonitor] "C:\Programmi\Microsoft Office\Office12\GrooveMonitor.exe"
O4 - HKLM\..\Run: [DATAMNGR] C:\PROGRA~1\IMESHA~1\MediaBar\Datamngr\DATAMN~1.EXE
O4 - HKLM\..\Run: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
O4 - HKLM\..\Run: [sqixe.exe] "C:\WINDOWS\sqixe.exe"
O4 - HKLM\..\Run: [hrqgm.exe] "C:\WINDOWS\hrqgm.exe"
O4 - HKLM\..\Run: [qpbnj.exe] "C:\WINDOWS\qpbnj.exe"
O4 - HKLM\..\Run: [uqzdv.exe] "C:\WINDOWS\uqzdv.exe"
O4 - HKLM\..\Run: [cwwmi.exe] "C:\WINDOWS\cwwmi.exe"
O4 - HKLM\..\Run: [syyeq.exe] "C:\WINDOWS\syyeq.exe"
O4 - HKLM\..\Run: [ckwui.exe] "C:\WINDOWS\ckwui.exe"
O4 - HKLM\..\Run: [fiioy.exe] "C:\WINDOWS\fiioy.exe"
O4 - HKLM\..\Run: [Malwarebytes' Anti-Malware] "C:\Programmi\Malwarebytes' Anti-Malware\mbamgui.exe" /starttray
O4 - HKLM\..\Run: [ezmui.exe] "C:\WINDOWS\ezmui.exe"
O4 - HKLM\..\Run: [fbfqc.exe] "C:\WINDOWS\fbfqc.exe"
O4 - HKLM\..\Run: [xcnhu.exe] "C:\WINDOWS\xcnhu.exe"
O4 - HKLM\..\Run: [rutqy.exe] "C:\WINDOWS\rutqy.exe"
O4 - HKLM\..\Run: [cxmys.exe] "C:\WINDOWS\cxmys.exe"
O4 - HKLM\..\Run: [xcatv.exe] "C:\WINDOWS\xcatv.exe"
O4 - HKLM\..\Run: [xcvih.exe] "C:\WINDOWS\xcvih.exe"
O4 - HKLM\..\Run: [ewzaf.exe] "C:\WINDOWS\ewzaf.exe"
O4 - HKLM\..\Run: [urrdj.exe] "C:\WINDOWS\urrdj.exe"
O4 - HKLM\..\Run: [gckhp.exe] "C:\WINDOWS\gckhp.exe"
O4 - HKCU\..\Run: [uTorrent] "C:\Programmi\uTorrent\uTorrent.exe"
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [sqixe.exe] "C:\WINDOWS\sqixe.exe"
O4 - HKCU\..\Run: [hrqgm.exe] "C:\WINDOWS\hrqgm.exe"
O4 - HKCU\..\Run: [qpbnj.exe] "C:\WINDOWS\qpbnj.exe"
O4 - HKCU\..\Run: [uqzdv.exe] "C:\WINDOWS\uqzdv.exe"
O4 - HKCU\..\Run: [cwwmi.exe] "C:\WINDOWS\cwwmi.exe"
O4 - HKCU\..\Run: [syyeq.exe] "C:\WINDOWS\syyeq.exe"
O4 - HKCU\..\Run: [ckwui.exe] "C:\WINDOWS\ckwui.exe"
O4 - HKCU\..\Run: [fiioy.exe] "C:\WINDOWS\fiioy.exe"
O4 - HKCU\..\Run: [ezmui.exe] "C:\WINDOWS\ezmui.exe"
O4 - HKCU\..\Run: [fbfqc.exe] "C:\WINDOWS\fbfqc.exe"
O4 - HKCU\..\Run: [xcnhu.exe] "C:\WINDOWS\xcnhu.exe"
O4 - HKCU\..\Run: [rutqy.exe] "C:\WINDOWS\rutqy.exe"
O4 - HKCU\..\Run: [cxmys.exe] "C:\WINDOWS\cxmys.exe"
O4 - HKCU\..\Run: [xcatv.exe] "C:\WINDOWS\xcatv.exe"
O4 - HKCU\..\Run: [xcvih.exe] "C:\WINDOWS\xcvih.exe"
O4 - HKCU\..\Run: [ewzaf.exe] "C:\WINDOWS\ewzaf.exe"
O4 - HKCU\..\Run: [urrdj.exe] "C:\WINDOWS\urrdj.exe"
O4 - HKCU\..\Run: [gckhp.exe] "C:\WINDOWS\gckhp.exe"
O4 - HKUS\S-1-5-19\..\Run: [sqixe.exe] "C:\WINDOWS\sqixe.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [hrqgm.exe] "C:\WINDOWS\hrqgm.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [kqylg.exe] "C:\WINDOWS\kqylg.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [qpbnj.exe] "C:\WINDOWS\qpbnj.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [uqzdv.exe] "C:\WINDOWS\uqzdv.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [cwwmi.exe] "C:\WINDOWS\cwwmi.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [syyeq.exe] "C:\WINDOWS\syyeq.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [fiioy.exe] "C:\WINDOWS\fiioy.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [ezmui.exe] "C:\WINDOWS\ezmui.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [fbfqc.exe] "C:\WINDOWS\fbfqc.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [xcnhu.exe] "C:\WINDOWS\xcnhu.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [wjlmx.exe] "C:\WINDOWS\wjlmx.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [dpnai.exe] "C:\WINDOWS\dpnai.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [rutqy.exe] "C:\WINDOWS\rutqy.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [cxmys.exe] "C:\WINDOWS\cxmys.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [xcatv.exe] "C:\WINDOWS\xcatv.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [xcvih.exe] "C:\WINDOWS\xcvih.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [ewzaf.exe] "C:\WINDOWS\ewzaf.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [urrdj.exe] "C:\WINDOWS\urrdj.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [crrab.exe] "C:\WINDOWS\crrab.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\Run: [gckhp.exe] "C:\WINDOWS\gckhp.exe" (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-20\..\Run: [sqixe.exe] "C:\WINDOWS\sqixe.exe" (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\S-1-5-18\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - HKUS\.DEFAULT\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'Default user')
O4 - Global Startup: HP Digital Imaging Monitor.lnk = C:\Programmi\HP\Digital Imaging\bin\hpqtra08.exe
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O8 - Extra context menu item: Free YouTube Download - C:\Documents and Settings\pinotto\Dati applicazioni\DVDVideoSoftIEHelpers\freeyoutubedownload.htm
O8 - Extra context menu item: Free YouTube to Mp3 Converter - C:\Documents and Settings\pinotto\Dati applicazioni\DVDVideoSoftIEHelpers\freeyoutubetomp3converter.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_06\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_06\bin\ssv.dll
O9 - Extra button: Invia a OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~2\Office12\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: I&nvia a OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~2\Office12\ONBttnIE.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\Office12\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
O18 - Protocol: grooveLocalGWS - {88FED34C-F0CA-4636-A375-3CB6248B04CD} - C:\Programmi\Microsoft Office\Office12\GrooveSystemServices.dll
O20 - AppInit_DLLs: C:\PROGRA~1\IMESHA~1\MediaBar\Datamngr\datamngr.dll C:\PROGRA~1\IMESHA~1\MediaBar\Datamngr\IEBHO.dll
O22 - SharedTaskScheduler: Precaricatore Browseui - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\system32\browseui.dll
O22 - SharedTaskScheduler: Daemon di cache delle categorie di componenti - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\system32\browseui.dll
O23 - Service: Avira AntiVir Scheduler (AntiVirScheduler) - Avira GmbH - C:\Programmi\Avira\AntiVir Desktop\sched.exe
O23 - Service: Avira AntiVir Guard (AntiVirService) - Avira GmbH - C:\Programmi\Avira\AntiVir Desktop\avguard.exe
O23 - Service: ASUSKeyboardService - ASUSTeK COMPUTER INC. - C:\WINDOWS\asuskbservice.exe
O23 - Service: MBAMService - Malwarebytes Corporation - C:\Programmi\Malwarebytes' Anti-Malware\mbamservice.exe
O23 - Service: NMSAccessU - Unknown owner - C:\Programmi\CDBurnerXP\NMSAccessU.exe
O23 - Service: %NVSVC.name% (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe

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End of file - 11714 bytes

Il tuo pc è letteralmente devastato da ogni genere di porcheria.
Anche cercando di bonificarlo, qualcosa rimarrà in ogni caso.
Il mio consiglio è quello di formattare,

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Se fai la rimozione manuale,devi eliminare anche i file associati.
MBAM dovrebbe facilitarti il lavoro. Eseguilo nelle modalità suggerite da cbbusto, prima di usare HJTH.

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