The inability to open a website by name usually indicates a DNS (Domain Name System) problem. DNS is the service that converts the website URL, i.e. www.yahoo.com into the IP address that is needed for actual communication.
A quick way to test this is to try to
access the problem website via its IP
address instead of its name. You can find a website’s
IP address by opening a Windows MS-DOS
or Command
prompt and typing ping,
followed by the website domain you are trying to reach (don’t type the www,
though). Here’s an example using google.com :
C :\Windows>ping
google.com
Pinging
google.com [216.239.51.100] with 32 Bytes of data :
Reply
from 216.239.51.100 : Bytes=32 time=267ms TTL=242
Reply from 216.239.51.100 : Bytes=32 time=261ms TTL=242
Reply from 216.239.51.100 : Bytes=32 time=256ms TTL=242
Reply from 216.239.51.100 : Bytes=32 time=252ms TTL=242
Reply from 216.239.51.100 : Bytes=32 time=261ms TTL=242
Reply from 216.239.51.100 : Bytes=32 time=256ms TTL=242
Reply from 216.239.51.100 : Bytes=32 time=252ms TTL=242
Ping
statistics for 216.239.51.100 :
Packets : Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds :
Minimum = 252ms, Maximum = 267ms, Average = 259ms
Packets : Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds :
Minimum = 252ms, Maximum = 267ms, Average = 259ms
You can see that 216.239.51.100 is google.com’s IP
address, so now enter http://216.239.51.100/
into your web browser’s address or location box. If the website comes up,
you’ve got a DNS problem.
Fixing DNS
The most common cause of the behavior
described above is incorrect DNS settings in your computer’s TCP/IP properties.
This typically happens after installing a hardwarerouter or Internet Sharing software
like Windows’ Internet Connection Sharing feature. If your computer had its TCP/IP properties set manually
(statically), you’re likely to have DNS-related problems.
The reason for the problem is that sharing
devices (and programs) usually like to handle DNS duties as part of their
sharing functions, and need to have computers that are connected to them set up
to get their DNS services from the router
(or sharing program) instead
of your ISP. Even though most people follow the router setup instructions and
change their network adapter TCP/IP settings to "Obtain an IP address automatically",
they commonly may neglect to clear
out the DNS settings, which in Win98 are located on the DNS Configuration
tab of the Network Properties window. WinXP makes it harder to forget to clear
any manual DNS settings that you may have, since it puts IP address, default
gateway, and DNS settings in the same window.
Fixing the problem is easy. Here’s how for Win95 and 98 :
1)
Right click on the Network Neighborhood
icon on your desktop and choose Properties.
A window similar to Figure 1
will open.
Figure
1 : Win98SE TCP/IP properties
2)
Scroll down the window in the Configuration tab
until you find the copy of TCP/IP that is bound (indicated by ->)
to the network adapter that you are using to connect to your network. You
should be able to recognize the correct adapter, since it will usually have
some sort of manufacturer’s name in it. Click on the adapter to select, then
click the Properties
button. Another window similar to Figure
2 will appear.
3)
The IP Address tab will probably have the Obtain an IP address automatically
radio button selected. Click on the DNS
Configuration tab.
Figure
2 : Win98SE DNS properties
4)
Figure 2 shows that the old DNS settings (your will
probably be different from the screenshot) are still in charge. Fix this by
deleting all entries in the DNS
Server Search Order box. Then click the Disable DNS
button. While you’re at it, click on the Gateway tab, and make sure there are no entries
there. Click the OK
button to close the TCP/IP properties
window, then click the OK
button to close the Networkproperties
window. Restart your system when prompted.
5)
After the system restarts, it’s possible that your computer may still have old
IP address information that can result in the same behavior as before. To force
the system to get new IP address information click Start > Run and type winipcfg.
Click the More Info button.
Select your network adapter, click the Release button, wait until the information in the
window is cleared, then click the Renew
button. After a short delay you should see new information in the window. (This
is called a DHCP Release / Renew.)
6)
Now open your web browser and try your problem sites. The problem should be
fixed. If it isn’t, see the What Else can be
wrong ? section below.
Here’s the fix for WinXP :
1)
Open the Network Connections
Control Panel. Double click on the Local
Area Connection icon in the LAN or High-Speed Internet
section of the Network Connections window that opens. Click on the Properties
button of the Local Area Connection Status window that opens. You should see
another window similar to Figure
3 open.
Figure
3 : WinXP Local Area Connection properties
2)
Click on the Internet Protocol
(TCP/IP) item to select it and click the Properties
button. A new window similar to Figure
4 should open.
Figure
4 : WinXP TCP/IP properties
3)
All you need to do is click the Obtain
DNS server address automatically button (the static DNS server information
will automatically be cleared). Click OK in each of the TCP/IP
and Local Area Connection
properties windows to close them.
4)
Once again, we want to be sure that we now have new IP address information. You
should still have the Local
Area Connection Status window open. Click the Support
tab, then click the Repair button.
After a short delay, you should get a repair completed popup and IP address
information should reappear in the window. You’ll need to click the Details...
button to see the DNS server information.
5)
Now open your web browser and try your problem sites. The problem should be
fixed. If it isn’t, see the What
Else can be wrong ? section below.
What Else can be wrong ?
If only all problems were so
straightforward ! But, unfortunately, bogus DNS settings in your computers
aren’t always the problem. Here are some other possible causes and actions to
take if you’re having problems accessing certain websites :
ISP
DNS problems
If things were working correctly with your exact same network setup, and then mysteriously stopped working, it’s possible that your ISP’s DNS servers are having problems. Contact your ISP’s tech support to report the problem and ask them to fix it !
If things were working correctly with your exact same network setup, and then mysteriously stopped working, it’s possible that your ISP’s DNS servers are having problems. Contact your ISP’s tech support to report the problem and ask them to fix it !
Proxy
problems
This also tends to fall into the ISP
problem category. Some ISPs (AOL for example) make all their subscribers run
through a proxy server.
Proxies sit between you and the actual Internet and are used both to locally
store (cache) content that doesn’t change very often and, in some cases,
prevent access to certain websites and web services. Most of the time proxies
operate without your knowing they’re even there, but sometimes they get
confused and cause problems.
You can see if you’re using a proxy by checking the Internet Options Control Panel, selecting the Connections tab, and clicking the LAN Settings... button. If any of the checkboxes are checked on the window that opens, you’re probably using a proxy. You can try clearing the checkboxes (write down the settings first or grab a screenshot), then quitting and restarting your browser and see if that helps. But if your ISP requires use of a proxy and doesn’t allow you to bypass it, this won’t help. Again, your option will be to contact your ISP’s support and tell them your problem.
You can see if you’re using a proxy by checking the Internet Options Control Panel, selecting the Connections tab, and clicking the LAN Settings... button. If any of the checkboxes are checked on the window that opens, you’re probably using a proxy. You can try clearing the checkboxes (write down the settings first or grab a screenshot), then quitting and restarting your browser and see if that helps. But if your ISP requires use of a proxy and doesn’t allow you to bypass it, this won’t help. Again, your option will be to contact your ISP’s support and tell them your problem.
Content
filtering
Although more popular in work-settings, content or website filtering is also available on a simpler basis for consumer router and Internet sharing applications. This function allows particular domains or website pages to be blocked to some, or all users. In many cases you won’t get an indication that the web page you’re trying to reach is being blocked and the router will just hang.
Again, if you don’t control your Internet access, there’s not much you can do about this one. A web-browsing proxy service may get you past any filters set up by Mom or Dad, but savvy network admins will probably have those websites blocked too.
Although more popular in work-settings, content or website filtering is also available on a simpler basis for consumer router and Internet sharing applications. This function allows particular domains or website pages to be blocked to some, or all users. In many cases you won’t get an indication that the web page you’re trying to reach is being blocked and the router will just hang.
Again, if you don’t control your Internet access, there’s not much you can do about this one. A web-browsing proxy service may get you past any filters set up by Mom or Dad, but savvy network admins will probably have those websites blocked too.
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