Mi compare sempre lafinestra che no è stato trovato il file:nsclib.dll, ho eseguito la scansione e ho trovato dei virus, che ho eliminato così ho proceduto ad eseguire la procedura per trovare l'errore, questo è il risultato:
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 18.54.54, on 01/10/2003
Platform: Windows XP (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 (6.00.2600.0000)
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\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\System32\urdvxc.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\ServicePackFiles\winlogon.exe
C:\WINDOWS\ServicePackFiles\winlogon.exe
C:\WINDOWS\ServicePackFiles\winlogon.exe
C:\Programmi\Alice ti aiuta\bin\mpbtn.exe
C:\Programmi\ClamWin\bin\ClamWin.exe
C:\Programmi\Microsoft Office\Office\WINWORD.EXE
C:\WINDOWS\msagent\AgentSvr.exe
C:\Documents and Settings\Elisa\Impostazioni locali\Temp\Directory temporanea 1 per HiJackThis.zip\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://g.msn.it/0SEITIT/SAOS01?FORM=TOOLBR
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://g.msn.it/0SEITIT/SAOS01?FORM=TOOLBR
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://google.com/
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://g.msn.it/0SEITIT/SAOS01?FORM=TOOLBR
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = 127.0.0.1
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
F3 - REG:win.ini: run=C:\WINDOWS\ServicePackFiles\winlogon.exe
O2 - BHO: bho3 Class - {58FB2CBB-C874-45FC-A1C9-B62CC9E3BED9} - C:\WINDOWS\system32\927194717.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Windows Live Toolbar Helper - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Programmi\Windows Live Toolbar\msntb.dll
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINDOWS\System32\msdxm.ocx
O3 - Toolbar: Windows Live Toolbar - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Programmi\Windows Live Toolbar\msntb.dll
O4 - HKLM\..\Run: [xem] C:\WINDOWS\ServicePackFiles\winlogon.exe
O4 - HKLM\..\Run: [ClamWin] "C:\Programmi\ClamWin\bin\ClamTray.exe" --logon
O4 - HKCU\..\Run: [xem] C:\WINDOWS\ServicePackFiles\winlogon.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 - Global Startup: Alice ti aiuta.lnk = C:\Programmi\Alice ti aiuta\bin\matcli.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Programmi\Microsoft Office\Office\OSA9.EXE
O8 - Extra context menu item: &Windows Live Search - res://C:\Programmi\Windows Live Toolbar\msntb.dll/search.htm
O9 - Extra button: Related - {c95fe080-8f5d-11d2-a20b-00aa003c157a} - C:\WINDOWS\web\related.htm
O9 - Extra 'Tools' menuitem: Show &Related Links - {c95fe080-8f5d-11d2-a20b-00aa003c157a} - C:\WINDOWS\web\related.htm
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - https://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab
O20 - AppInit_DLLs: C:\WINDOWS\System32\systp.dll c:\windows\system32\ldcore.dll
O20 - Winlogon Notify: crypt - crypts.dll (file missing)
O23 - Service: Distributed Allocated Memory Unit - Unknown owner - C:\WINDOWS\system32\dllcache\mravsc32.exe (file missing)
O23 - Service: Local Service - Unknown owner - C:\WINDOWS\wuaurpl.exe (file missing)
O23 - Service: ms hexidecimal defx (mshexdefx) - Unknown owner - C:\WINDOWS\system32\dllcache\ivchost.exe (file missing)
O23 - Service: Network Windows Service (MSWindows) - Unknown owner - C:\WINDOWS\System32\urdvxc.exe

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End of file - 4157 bytes

Scusa, ma mi spieghi tutto questo cosa ha a che fare con il titolo "non é permesso formattare il disco C"?