Internet Connection Problem

yestrday i made a clean install of windows 7 build 7600.
My problem is very wierdly i can connect to the internet thru my wireless network no problem. I can surf most sites no problem. But the problem is all of the anti virus programs (kaspersky, nod32) spyware detectors(ad-aware, antisuperspyware) i tried, When they try to update their database, They can not connect. Also for windows update it can not connect. I tried turning of firewall, didnt help.(i dont have anything else other then windows standart firewall) I searched for viruses thinking maybe its kind of virus but nothing. When i ping those update servers for example u20.eset.com
it doesnt resolve the ip instead it resolves as 127.0.0.1 and the answer comes from 127.0.0.1 from my own computer. How can i fix that its very annoying thanks.

It seems very strange that your AV and Windows Update software doesn't work... Can you try and run an online virus scan and see if that detects anything (and this will check if that site has been blocked):

http://housecall.trendmicro.com/

Also, can you open your hosts file and see if there are any extra entries in there (other than localhost):

The file is located here : %WINDIR%\System32\Drivers\etc\Hosts

thanks mate.
i have already checked host file nothing extra.
and no virus found.

What happens when you ping the following domains : u20.eset.com, eset.com, google.com?

Does only the last one resolve properly? If so, I'd do a complete clean install (not with the same source) as you could well have a W7 install that has been tampered with. Many viruses prevent access to AV websites and update services, so if only those domains point to your local IP then something is very wrong.

google resolves properly, eset.com and u2.eset.com resolves 127.0.0.1
kaspersky.com, symantec.com also resolves properly but kaspersky update server doesnt. I havent tried others.
I had a lot of problems when installing w7 so i would like to have making a clean install again reserved as the last option. I scaned for viruses with nod32 and kaspersky2010 with the updated databases (i downloaded them to another computer and then made an offline update to my w7) and they didnt found anything.

i have just tried connecting to internet via my cell phone thru 3G instead of my regular wireless connection. And i was able to download the updates.

sorry everyone for taking your time. Problem solved.
i just changed my dns servers to opendns servers and problem solved.
Thank you Ian for your help.

Glad it's working now Out of interest, were the initial problematic DNS servers ones you had set yourself?

automatic, my isp's servers. still wierd though they would be blocking these sites, doesnt make sense.

If you ever have problems with malware and you are not sure if your computer is protected, try this free tool: http://quickscan.bitdefender.com/
No need for download.. and scanning takes only 30 seconds. To remove any detected malware, you can download BitDefender Internet Security 2009 and try it free for one month. I use it, and I had no problems with malware in the last 3 months.