Hello. There is Windows Server 2008 Enterprise x64. Few days ago some applications, e.g. BOINC Manager, Gene6 FTP Administrator, MySQL client, had stopped working: they cannot connect to localhost. My investigation has found, that ping 127.0.0.1 fails (command ping localhost pings only IPv6 ::1). I had no new software installed except Web Platform Installer. Also I did a registry editing about concurrent PPPoE connections limitation (set 1 to 2). Could it kill Loopback Adapter? But in RRAS console it's shown well and listening ports are shown too. I had rollback the changes, reboot but it doesn't help. The HOSTS file contains 2 records: just localhost for IPv4 and IPv6. Some time before I got a bug in Windows Defender, it was indicating that hosts records been hostile, but later this notification missed. Could you please tip me how to fix such issue?

hi there, can you please post your query in english as this forums are w.r.t english.sainath Windows Driver Development

hi there, can you please check if you are able to ping in "safe mode with networking " mode ( please do restart theserver and during boot press F8 for boot options and then select "safe mode with networking " and do let us know the output.sainath Windows Driver Development

Hello. Yes, ping localhost works absolutely properly in the Safe Mode with Networking. In normal mode - doesn't! Also I have SP2 installed but it didn't helped too.

And all other interfaces (2 network cards + 2 PPPoE connections) can be pinged without problems