Windows Defender detected malicious software - Category : Settings Modifier in files -C:\Windows\winsxs\x86_microsoft-windows-w..nfrastructure-other_31bf3856ad364e35_6.0.6000.16386_none_024e4071fa6fea95\hosts.Alert Level - Medium.Options available - Clean, Remove , Quarantine.Whenasked to clean,Defender reports - Error encountered: Code 0x80508017 .Some actions couldn't be applied to potentially harmful items. Help and Support suggests manually re-writing hosts file.I'm a newbie.Is it safe for me to do so manually or should I ask Windows Defender to "Remove" it as it may be an important system32 file? My OS is Windows Vista Premium - Service Pack 1 & I'm runing Kaspersky Internet Security 2009 version 8.

Hi Raven115, we can manually remove the files under the hosts folder. Meanwhile, I also suggest you first try a free online virus scan on the following site: http://safety.live.com If you need more help with virus/malware related issues, please contact Microsoft Product Support Services. For support within the United States and Canada, call toll-free (866) PCSAFETY (727-2338). For support outside the United States and Canada, visit the Product Support Services Web page (http://support.microsoft.com/?pr=SecurityHome ). Hope this helps!Sean Zhu - MSFT

HiRaven115,Perhaps a False Positive of Windows Defender.See:http://www.malwarebytes.org/forums/index.php?showtopic=12390andSettingsModifier:Win32/PossibleHostsFileHijackSignature versions 1.53.283.0 and higher of WD include the fix to the False Positive.Hope this helps,Vincenzo Di Russo - Microsoft MVP Windows Internet Explorer, Windows Desktop Experience & Security - Since 2003. ~ My Blog: http://blogs.dotnethell.it/vincent/