Network and internet problems

I use the internet normally from my pc, but after a while, my browser stop functioning and every website i try to browse i always get the following errors

Error 100 (net::ERR_CONNECTION_CLOSED): Unknown error.

Error 105 (net::ERR_NAME_NOT_RESOLVED): The server could not be found.

Error 109 (net::ERR_ADDRESS_UNREACHABLE): Unknown error.

but when i try to browse from other pcs on the same network, its working fine, so its definelty a problem with my PC

My PC specs
OS =  Winxp/ sp2
anti virus : Bit defender
Other applications
Office 2003
Visual studio 2008
Sql 2000 and sql 2005

LVL 15
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chicka616Connect With a Mentor Commented:
It might be bitdefender.
Close that AV program and see if you can browse the internet after...
That will prove if Bitdefender is the culprit.
possibly this could help

have you been playing with proxy settings?
Hi there;

well, prior going to depths, I recommend first updating your sp2 to the latest, maybe sp3 directly.
which internet browser are you using? If it's an old one, I recommend updating that too.

Best regards.
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Does rebooting the pc solve the problem for awhile? When your having this problem can you reach other devices on your internal network?  When I see these errors I think of the tcp stack.
Name not resolved, that's DNS related, Address unreachable, that's routing related, connection closed that's tcp related.  All of these relate back to the tcp stack. Are you familiar with the commands ipconfig, ping, pathping, nslookup, tracert, arp and route print?  If not, these can all help with troubleshooting tcp related problems.

1st of all check you are getting IP address from DHCP ( Run> ipconfig)
If  no set manual and follow steps
Run > CMD >Ping
        > Ping
        > Tracert
If you are not getting IP , reset Winsock
write result here of above test
AmmarRAuthor Commented:
thanks AK2009:

the error message is same but its not the same problem,

i am thinking of remove bitdefender, because it made many problems for me any way, but i need to leave my pc switched on for a while to see if the problem still exists or has gone forever


yeah after i reboot, the problem is solved, how can i check  tcp stack problems


when the problem happens i tried many solutions but none work, only after restarting

i tried
Ipconfig / release and ipconfig / renew

i tried
disabling and enabling the [local Area network] so i get a new ip

i tried repair  [local Area network]

but none worked

farjadarshadConnect With a Mentor Commented:
did you try with any other browser like firefox, safari or chrome. if the same problem occur in them as well then move on to start >> run and type sfc /scannow but before this don't forget to put windows bootable cd in the cd rom drive.

Also check by stopping bitdiffender. On the second thought also check your system for spywares and malwares for which use following tools

1. Malewarebytes >>
2. Superantispyware >>
3. Hitmanpro's Surfright >>
4. Hijack this >>         
5. Combofix >>          
6. Bitdefender >>      
7. SPybot                  
8. CCleaner               
9. Registry Cleaner   
10. Defraggler           

Also install antivirus one of the following but remove bitdiffender first

1.ESET Nod32 (most recommended)
2.Symantec Endpoint
3. Norton 360
in last if no luck then repair your windows as shown in the link below

hope this will help you
Did you try resetting WINSOCK ??
If not try it 1st

We need some info from you on what you see when you run these commands.

First I'd run these when I was not having the problem.  Sort of a baseline when things are working, so you have something to compare things with.
You can copy and paste the results from the shell into Wordpad or Notepad.
Then run them again when your having the problem and save those results to Notepad.

Run these cmds to check out the stack. Get to the cmd prompt.
ipconfig /all   does it return what you expect to see?  
Then ping by name, this will test DNS.  Does the name resolve?  
If not what msg do you get?
Then ping by ip address. Do you get a reply back?
If not what msg do you get? Time out? Destination host not found?
ipconfig /flushdns run this cmd then try the steps again.  Might be DNS related and flushing the cache may help.

Check out your routing when it's working, run tracert so you can see what path the hops take.
You want to make sure you can at least reach your router, and then on out to the internet.

Here's a link that has instructions on resetting the stack if you need to. How to reset Internet Protocol (TCP/IP)

And and a deep malware scan can't hurt.  You could have something on there that's screwing with your stack.  
If all else fails consider,removing the drivers for the nic and reboot. The Found New Hardware wizard starts.  Reinstall the card with the latest drivers. . Bind TCP/IP to the card.
AmmarRAuthor Commented:
Dear farjadarshad: & mobot:

i am trying what you suggested, but i need to wait until the problem reoccur

how can i reset WINSOCK
>> Start, Run, CMD to open a command prompt.

Reset WINSOCK entries to installation defaults: netsh winsock reset catalog

Reset TCP/IP stack to installation defaults. netsh int ip reset reset.log

Another easy way to test that stack is to simply ping localhost it should return  Good luck :)
AmmarRAuthor Commented:
Thanks allot Guys

i am just waiting for the problem to reoccur and check which solution is going to fix it,

AmmarRAuthor Commented:
Hi all

the problem happened again and tried all the above solutions without any result
the problem is i am Connected to Internet but Browser not working

i tried pinging and tracert and ipconfig /all ipconfig/flushdns etc
i can see results when i ping and or tracert

but my browsers are not working
i tried winsock reset, still not working
i tried disabling bitdefender and no results
i have 5 browesrs on my machine, and all are not working, i just get a black screen where ever i try to browse

Internet explorer

but the funny part is, i tried google talk and FTP client and they work fine ????

i searched alot on the internet and no real solution yet??????
Alan HardistyCo-OwnerCommented:
Hi AmmarR - I saw your request for attention and thought I would see if I could assist you.  I'm about to head out with the family, so may be away for a few hours in about half an hour, but will respond as and when I can.
Please run the following command on your machine and at least one working machine then upload the c:\ipconfig.txt files so that I can see what your IP settings are:
IPCONFIG /all >c:\ipconfig.txt
AmmarRAuthor Commented:

i ran this command several times ipconfig /all

its working fine and i get an ip from the router and my router is working fine.

because other machines in the network are working fine.

and as i mentioned, FTP and Google talk are working.

so if you want to know whether i get an IP or not, i do get.

i ran
ipconfig / flushdns
Ipconfig /release
ipconfig /renew

browsers still dont work???
Alan HardistyCo-OwnerCommented:
I would like to see what you have got setup - just to make sure all is well.  Please post the information I have requested.
Once I know that is okay - I can move on to the next step.
delete file name "hosts" from

AmmarRAuthor Commented:
I dont really know the real cause of the problem or why it happened.

i tried all the solutions suggested by the experts but it still continued happeneing.

at the end i completely removed the antivirus Bitdefender and since i removed it, it stopped occuring now for about a week.

So i am assuming its because of bitdefender.

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