I'm running Windows 2000 or Windows XP and I keep getting "Can't display page (Server or DNS error)" when browsing even though I KNOW that there is a DNS entry for that web page.

The problem here sometimes is due to Microsoft's DNS Client that comes with Windows 2000 and Windows XP, which "caches" the IP addresses of web pages you've visited.

DNS is the "address book" of the Internet. Computers like numbers, and humans like words. So, DNS was invented to translate between the two worlds. It's much easier for us to remember humboldt1.com instead of the IP address of 206.13.45.1.

So, everytime you go to a web page, your computer asks the DNS server, "Hey, what's the IP address of so-and-so.com?" The server tells your computer, and then your computer connects to so-and-so.com's server.

Problem #1

The problem is that your computer has to ask the DNS server for the IP address EVERY TIME you go to a new web page.

For example, when you browse to a couple of web pages on humboldt1.com, such as:

http://www.humboldt1.com
http://www.humboldt1.com/tutorials

your computer would need to ask a DNS server, "Hey, what is www.humboldt1.com's IP address?" THREE times. Your computer should know it by now. And it does! The DNS Client remembers the IP addresses by "caching" or "remembering".

Problem #2

Unfortunately, that causes yet another problem in Windows 2000 and XP. Microsoft has installed a "DNS client" that not only remembers the IP addresses of the web pages you've been to, but also it remembers the errors.

Consider this scenario:
You try to go to a web page, and your computer asks our DNS server what the IP address of that web page is. If our DNS server doesn't already know what the IP address is, it asks another DNS server "Psst, hey, do you know the IP address of that web page?" And, if the second one doesn't know either, he says, "No, I don't, but ask that other server over there." So our server asks that server over there. However, that server over there is temporarily down for some reason, so our DNS server can't find the IP address, and it tells your computer, "Sorry, I can't find the IP address of that web page", and you get "Can't display page" error.

Bummer.

The DNS Client on your computer caches that error, so the next time you try to go to that web page, your computer doesn't even bother our DNS Server because the DNS Clent says, "Nope, sorry. We don't know the IP address of that web page". EVEN THOUGH that other server over there is back up and running.

The Fix

SOoooo, how do we fix this?
Welp, here are a couple of suggestions..

Try again later - The DNS Client only caches it's information for a short time. So trying later will alow that cache entry to expire.
Reboot your computer - The cache is cleared when the computer gets turned off.
Clear the DNS cache manually - Go to the Start Button->Run and type in "ipconfig /flushdns" (withOUT the quotes) and viola!
Turn off the DNS Client entirely - Though this might not be the best idea because we go back to Problem #1
The BEST solution would be if we could disable the portion of the DNS client that caches the pages that have errors on them. But this is well outside the scope of this document and Humboldt Internet will not support modifications like these.

These suggestions come from TechTV's website and the latest link we have for them is this article.

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