Can't access any web sites

[DavePL]

My new computer was working fine for several months, now all of a sudden I can't browse anywhere. I'm running WinXP-SP2, and don't seem to have any spyware or viruses. My external serial modem dials up fine and connects at 48Kbps. I disabled the firewall, tried disabling antivirus, ran winsocket fix, reinstalled/repaired windows xp, removed and reinstalled SP2. Tried a different ISP, changed access numbers, ran Firefox. Nothing seems to help. I could try a different modem. I'm almost ready to reformat the hard drive, and was hoping someone may know of other possible trouble shooting methods?

 

[ChrisAC]

Can you resolve DNS okay?

Chris.

**********************
Chris A.C, CCNA, CCSA
**********************

 

[DavePL]

Good suggestion. I will try running: nslookup yahoo.com at the command prompt, as desribed earlier in this forum, and see if that works. Much appreciate the comments.

 

[DavePL]

Yes, it seems I cannot resolve DNS. Running "nslookup yahoo.com", gives "no response from server", "server unknown", "default servers are not available". It knows the IP address of my DNS server, but cannot ping it. If I type in the IP address of a web site in my browser, it connects, though very slow. Running "ipconfig /all" shows I have obtained an IP address, gateway, and DNS server.

On my other windows 98 machine, DNS works normally, and I can ping the DNS server.
I would appreciate any suggestions on why I can't connect to the DNS server?

 

[MaxPipeline]

Any PC firewalls? If so then perhaps the firewall is blocking DNS access to the Internet. Otherwise you can try rebuilding your TCP/IP stack. To do this uninstall TCP/IP, reboot, then reinstall TCP/IP. You may need the Win98 CD (it's been a while since I worked with Win98).

 

[DavePL]

Actually I tried disabling the firewall which didn't help.
However I was able to fix the DNS problem by reinstalling TCP/IP as you suggested. Since I have Windows XP, it wasn't as simple as Win98, and involved disabling and re-enabling it, and then finally I was able to reach some web sites! I ran nslookup at the command prompt as before, and the DNS problem seems fixed.
Another thought would be to uninstall everything network related (except the modem drivers) and then reinstall everything. Will try that if the problem occurs again.

 

[sylve]

Can you ping yahoo.com and yahoo.com's IP now?
What is your route print?
Have you tried disabling everything in msconfig?
Can you post the link to the exact winsock fix you used?

What happpened just before you started having this problem (installing new games, sp2... anything).

 

[sylve]

Before formatting, try this. If you can ping yahoo.com's ip but not the DNS, here is a regfix (what the winsock fix is SUPPOSE TO DO). This reinstalls your tcp/ip:


-Delete these keys:
hkey_localmachine/system/currentcontrolset/services/winsock
hkey_localmachine/system/currentcontrolset/services/winsock2

-reboot your computer
-go into your LAN properties. Click install, choose protocol then ADD
-click on have disk
-in "copy manufacturer's files" type C:\Windows\inf
-hit ok. choose Internet protocol TCP/IP
-reboot your computer

-try to browse


IMPORTANT: Create a backup registry file with "File-->export" before doing this. If something goes wrong, you can restore via safe mode

 

[DavePL]

I found I had another problem, involving firewalls blocking my service. I have Zone Alarm, in addition to the built-in Windows firewall. They both were turned off, and yet somehow they were still blocking my ISP. I configured them allow full access to my ISP software, and that finally fixed the problem. How the firewalls can slow down the service when they are off I can't explain, but configuring them did solve the problem. DNS is working now also.