da questa mattina che ho acceso il pc e ora dopo 4 ore di lavoro è diventato di una lentezza esasperante non ho programmi in esecuzione vi posto il Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 15.57.43, on 07/03/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16608)
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\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\Grisoft\AVG Anti-Spyware 7.5\guard.exe
C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
C:\PROGRA~1\Grisoft\AVG7\avgemc.exe
C:\Programmi\COMODO\Firewall\cmdagent.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\rundll32.exe
C:\PROGRA~1\Grisoft\AVG7\avgcc.exe
C:\Programmi\COMODO\Firewall\cfp.exe
C:\Programmi\Grisoft\AVG Anti-Spyware 7.5\avgas.exe
C:\DOCUME~1\user\IMPOST~1\Temp\Rar$EX00.766\firefox-ultimate-optimizer-11\Firefox Ultimate Optimizer.exe
C:\Programmi\Mozilla Firefox\firefox.exe
C:\Programmi\hijackthis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
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 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
R3 - URLSearchHook: Yahoo! Toolbar con blocco Pop-Up - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - (no file)
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_05\bin\ssv.dll
O2 - BHO: (no name) - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - (no file)
O4 - HKLM\..\Run: [Cmaudio] RunDll32 cmicnfg.cpl,CMICtrlWnd
O4 - HKLM\..\Run: [CnxTrApp] rundll32.exe "C:\Programmi\StarModem\StarModem USB Network\CnxTrApp.dll",AppEntry -REG "Conexant\Conexant USB Network"
O4 - HKLM\..\Run: [AVG7_CC] C:\PROGRA~1\Grisoft\AVG7\avgcc.exe /STARTUP
O4 - HKLM\..\Run: [COMODO Firewall Pro] "C:\Programmi\COMODO\Firewall\cfp.exe" -h
O4 - HKLM\..\Run: [FirefoxUltimateOptimizer] "C:\DOCUME~1\user\IMPOST~1\Temp\Rar$EX00.766\firefox-ultimate-optimizer-11\Firefox Ultimate Optimizer.exe"
O4 - HKLM\..\Run: [!AVG Anti-Spyware] "C:\Programmi\Grisoft\AVG Anti-Spyware 7.5\avgas.exe" /minimized
O4 - HKLM\..\Run: [MSConfig] C:\WINDOWS\PCHealth\HelpCtr\Binaries\MSConfig.exe /auto
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-20\..\Run: [AVG7_Run] C:\PROGRA~1\Grisoft\AVG7\avgw.exe /RUNONCE (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: ERUNT AutoBackup.lnk = C:\Programmi\ERUNT\AUTOBACK.EXE
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MI1933~1\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
O20 - AppInit_DLLs: C:\WINDOWS\system32\guard32.dll
O20 - Winlogon Notify: !SASWinLogon - C:\Programmi\SUPERAntiSpyware\SASWINLO.dll
O23 - Service: AVG Anti-Spyware Guard - GRISOFT s.r.o. - C:\Programmi\Grisoft\AVG Anti-Spyware 7.5\guard.exe
O23 - Service: AVG7 Alert Manager Server (Avg7Alrt) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
O23 - Service: AVG7 Update Service (Avg7UpdSvc) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
O23 - Service: AVG E-mail Scanner (AVGEMS) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgemc.exe
O23 - Service: COMODO Firewall Pro Helper Service (cmdAgent) - COMODO - C:\Programmi\COMODO\Firewall\cmdagent.exe

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End of file - 4878 bytes

Il log sembra pulito, mi puzza questa riga, che ti consiglio di fixare:

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O4 - HKLM\..\Run: [FirefoxUltimateOptimizer] "C:\DOCUME~1\user\IMPOST~1\Temp\Rar$EX00.766\firefox-ultimate-optimizer-11\Firefox Ultimate Optimizer.exe"

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elimina il file associato e già che si sei, vuota la cartella temp.
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C:\DOCUME~1\user\IMPOST~1\Temp\Rar$EX00.766\firefox-ultimate-optimizer-11\Firefox Ultimate Optimizer.exe
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Ciao.

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