Strano problema con DNS

[maxx.monopoli]

Ciao,

da qualche tempo ho un problema con i browser (sia Firefox sia IE):
senza un'apparente ragione specifica, ogni tanto il browser non riesce a risolvere il nome dominio e quindi non trova il sito. Facendo riprovare 2 o 3 volte alla fine ce la fa.

Ho la sensazione che sia un virus o simile, ma non riesco a trovarlo.

Ho già fatto scansioni con Avira, AVG, Panda ActiveScan, Spybot e Superantispyware, il problema persiste.

Il PC è in una rete con altre macchine, c'è un firewall/NAT con IP fisso che funge da gateway per tutta la rete. Le altre macchine non hanno problemi.

Qui di seguito il log di HiJackThis:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 18.06.00, on 09/09/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
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\Avira\AntiVir PersonalEdition Classic\sched.exe
C:\Programmi\Avira\AntiVir PersonalEdition Classic\avguard.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\Programmi\CyberLink\Shared Files\RichVideo.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\Adobe\Acrobat 7.0\Distillr\Acrotray.exe
C:\Programmi\Avira\AntiVir PersonalEdition Classic\avgnt.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\SUPERAntiSpyware\SUPERAntiSpyware.exe
C:\PROGRA~1\HEWLET~1\Toolbox\STATUS~1\STATUS~1.EXE
C:\Programmi\Hewlett-Packard\Toolbox\jre\bin\javaw.exe
C:\Programmi\Mozilla Firefox\firefox.exe
C:\Programmi\Microsoft Office\OFFICE11\OUTLOOK.EXE
C:\Programmi\Trend Micro\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = about:blank
O2 - BHO: Supporto di collegamento per Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\File comuni\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_06\bin\ssv.dll
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Programmi\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [NeroFilterCheck] C:\Programmi\File comuni\Ahead\Lib\NeroCheck.exe
O4 - HKLM\..\Run: [Acrobat Assistant 7.0] "C:\Programmi\Adobe\Acrobat 7.0\Distillr\Acrotray.exe"
O4 - HKLM\..\Run: [avgnt] "C:\Programmi\Avira\AntiVir PersonalEdition Classic\avgnt.exe" /min
O4 - HKLM\..\Run: [TomcatStartup 2.5] C:\Programmi\Hewlett-Packard\Toolbox\hpbpsttp.exe
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [SUPERAntiSpyware] C:\Programmi\SUPERAntiSpyware\SUPERAntiSpyware.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')
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://www.update.microsoft.com/wind...?1214822440183
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://www.update.microsoft.com/micr...?1214830088828
O17 - HKLM\System\CCS\Services\Tcpip\..\{2FF6644A-CF96-45B2-843A-89CB59B35BA6}: NameServer = 213.140.2.43,213.140.2.49
O17 - HKLM\System\CS1\Services\Tcpip\..\{2FF6644A-CF96-45B2-843A-89CB59B35BA6}: NameServer = 213.140.2.43,213.140.2.49
O17 - HKLM\System\CS2\Services\Tcpip\..\{2FF6644A-CF96-45B2-843A-89CB59B35BA6}: NameServer = 213.140.2.43,213.140.2.49
O20 - Winlogon Notify: !SASWinLogon - C:\Programmi\SUPERAntiSpyware\SASWINLO.dll
O23 - Service: Avira AntiVir Personal - Free Antivirus Scheduler (AntiVirScheduler) - Avira GmbH - C:\Programmi\Avira\AntiVir PersonalEdition Classic\sched.exe
O23 - Service: Avira AntiVir Personal - Free Antivirus Guard (AntiVirService) - Avira GmbH - C:\Programmi\Avira\AntiVir PersonalEdition Classic\avguard.exe
O23 - Service: NMIndexingService - Nero AG - C:\Programmi\File comuni\Ahead\Lib\NMIndexingService.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: Cyberlink RichVideo Service(CRVS) (RichVideo) - Unknown owner - C:\Programmi\CyberLink\Shared Files\RichVideo.exe

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End of file - 4078 bytes


Qualche idea?

Grazie 1000
Maxx

[maxx.monopoli]

Avira, fino a poco tempo fa AVG