all application (FileZile, Firefox, IE, Chrome, Safari...) cannot perform DNS resolution, use IP address to brownses is working well. nslookup under command prompt is working well but ping also not able perform DNS resolution. ping to computer it's host name also not able resolute to IP. w

More information is needed. How is your DNS set up? Are you on a domain with a local DNS server or is DNS resolution handled by a router? Please post the results of an IPCONFIG /ALL so we can take a look at how your DNS is configured.

Router handle the resolution. Windows IP Configuration Host Name . . . . . . . . . . . . : HOME8-4 Primary Dns Suffix . . . . . . . : Node Type . . . . . . . . . . . . : Hybrid IP Routing Enabled. . . . . . . . : No WINS Proxy Enabled. . . . . . . . : No Ethernet adapter Local Area Connection 4: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller Physical Address. . . . . . . . . : 00-23-CD-B0-6A-24 DHCP Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes IPv4 Address. . . . . . . . . . . : 192.168.30.144(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Lease Obtained. . . . . . . . . . : Tuesday, February 01, 2011 11:12:53 PM Lease Expires . . . . . . . . . . : Wednesday, February 02, 2011 11:12:53 PM Default Gateway . . . . . . . . . : 192.168.30.1 DHCP Server . . . . . . . . . . . : 192.168.30.1 DNS Servers . . . . . . . . . . . : 192.168.30.1 NetBIOS over Tcpip. . . . . . . . : Enabledw

i guess my problem is after kb976902 has been installed. w

Ah, no, I don't think is was that update as that was a service stack update and had nothing to do with networking or DNS. It's more likely an issue with your router or ISP. Look in your router's WAN configuration page and get the IP addresses of your ISP's DNS servers and see if you can PING them. In fact, your router should have the ability to test its connection and do a DNS lookup of a site, so check that as well. If the DNS lookup from the router's test page fails then the problem's with your ISP or your router's settings. BTW, your IPCONFIG looks normal, so Windows is properly configured. Don't change anything there.

other device in my network are working well. i belive the router is working fine. this is so strange that localhost name and manual entry in hosts file also not able be resolve. w

user IP to connect LAN resource also not work . example: \\192.168.1.10 i believe there have something wrong to a network compoent of windows, not setting issue. p.s. i had uninstall follow software around the time of problem happen, i not sure weather related but just for reference 1. Symantec BackupExec System Recovery 2. VMServer 2.02 thank you w

Well no - 192.168.1.10 is on a different subnet than your PC and your netmask only allows for local communications on the same subnet (192.168.30.x). In order to communicate with that local address you'd need to change your subnet mask to 255.255.0.0, thereby broadening your subnet to include the other range. Try flushing your DNS cache: IPCONFIG /FLUSHDNS

sorry for typo, should be \\192.168.30.10 tried flush cache but doesn't help. there may be the hint that i cannot get resolve by ping to my hosts name. C:\Users\Owner>ping home8-4 Ping request could not find host home8-4. Please check the name and try again. w

What happens when you try to ping LOCALHOST? It should return your computer's name and the address 127.0.0.1 (or possibly ::1 if IPv6 is enabled) and not timeout. Also, try these two commands and post the results: nslookup nslookup www.microsoft.com

C:\Users\Owner>ping localhost Ping request could not find host localhost. Please check the name and try again ========================================================= C:\Users\Owner>nslookup Default Server: DD-WRT Address: 192.168.30.1 ========================================================= C:\Users\Owner>nslookup www.microsoft.com Server: DD-WRT Address: 192.168.30.1 Non-authoritative answer: Name: lb2.www.ms.akadns.net Addresses: 65.55.12.249 65.55.21.250 207.46.170.10 207.46.170.123 64.4.31.252 Aliases: www.microsoft.com toggle.www.ms.akadns.net g.www.ms.akadns.net w