Could not resolve hostname

Hi there,

I went throu all post, but didn´t found any solution for my problem, so I am asking for a help here.
I am using TS3 for 2 1/2 years without any problem. Few days a made new instaltion of Win7 x64 Ultimate (the same like previous), installed latest version od TS3 client, connected without problem to server I needed. After 2 days samothing went wrong and I am unable to connect to any server, even to search in server list. Here is my log. Please help me.

14.9.2015 20:38:58 Info TeamSpeak 3 Client 3.0.17 (2015-08-04 07:38:33)
14.9.2015 20:38:58 Info SystemInformation: Windows 7 SP1 (7601) x64 (AMD or Intel) Binary: 64bit
14.9.2015 20:38:58 Direct Sound Debug setting timer resolution to 1ms
14.9.2015 20:38:58 Info Loading plugin: clientquery_plugin
14.9.2015 20:38:58 Info Loading plugin: lua_plugin
14.9.2015 20:38:58 Info Loading plugin: teamspeak_control_plugin
14.9.2015 20:38:58 Info Loading plugin: test_plugin
14.9.2015 20:38:58 Info Loading plugin: ts3g15
14.9.2015 20:38:58 Query Info listening on 127.0.0.1:25639
14.9.2015 20:38:58 Windows Audio Session Devel DeviceDeleteList::waitForDeletes - enter
14.9.2015 20:38:58 Windows Audio Session Devel DeviceDeleteList::waitForDeletes - leave
14.9.2015 20:38:58 Input Info Default monitoring enabled
14.9.2015 20:38:58 Info *** Time [MAINWINDOW]: 315
14.9.2015 20:38:58 Info *** Time [INIT]: 315
14.9.2015 20:38:58 ClientUI Info Qt version: 5.4.1
14.9.2015 20:38:58 ClientUI Info Using configuration location: F:/TS3/config/settings.db
14.9.2015 20:38:59 ClientUI Info Last update check was: po 9 14 22:16:44 2015
14.9.2015 20:38:59 ClientUI Info Checking for update
14.9.2015 20:38:59 Update Info Checking for updates...
14.9.2015 20:38:59 Newsticker Info Newsticker language change detected
14.9.2015 20:38:59 Newsticker Info Newsticker next check:
14.9.2015 20:39:00 Newsticker Info Newsticker not found for language cs
14.9.2015 20:39:00 Info Statistics report: Not yet, next report on pá 10 2 16:39:38 2015
14.9.2015 20:39:00 Newsticker Info Newsticker not found for language en
14.9.2015 20:39:00 ClientUI Info Connect to server: 81.0.217.180
14.9.2015 20:39:00 ClientUI Info Blacklist check ok
14.9.2015 20:39:00 ClientUI Info Initiating connection: 81.0.217.180:6528 81.0.217.180
14.9.2015 20:39:00 Windows Audio Session Devel DeviceDeleteList::waitForDeletes - enter
14.9.2015 20:39:00 Windows Audio Session Devel DeviceDeleteList::waitForDeletes - leave
14.9.2015 20:39:00 Windows Audio Session Debug WAS::openDevice-enter
14.9.2015 20:39:00 Windows Audio Session Debug WAS Buffer size: 960
14.9.2015 20:39:00 Windows Audio Session Debug WAS::openDevice-leave
14.9.2015 20:39:00 Windows Audio Session Debug WAS::startDevice-enter
14.9.2015 20:39:00 Windows Audio Session Debug WAS::startDevice-leave
14.9.2015 20:39:00 Windows Audio Session Devel DeviceDeleteList::waitForDeletes - enter
14.9.2015 20:39:00 Windows Audio Session Devel DeviceDeleteList::waitForDeletes - leave
14.9.2015 20:39:00 Windows Audio Session Debug WAS::openDevice-enter
14.9.2015 20:39:00 Windows Audio Session Debug WAS Buffer size: 896
14.9.2015 20:39:00 Windows Audio Session Debug WAS::openDevice-leave
14.9.2015 20:39:00 PreProSpeex Info Speex version: speex-1.2beta3
14.9.2015 20:39:00 Windows Audio Session Debug WAS::startDevice-enter
14.9.2015 20:39:00 Windows Audio Session Debug WAS::startDevice-leave
14.9.2015 20:39:00 ClientUI Warning Error in ts3client_startConnection: could not resolve hostname (1798)

Could not resolve hostname