Windows 7: http 501/http 505

My Internet Explorer (v 8) connects without problem to every URL I enter, with one exception. Every time I attempt to connect to that one URL I get a message indicating http 501/http 505 error. Several days ago I was able to connect to that site without problem but all more recent attempts have failed as described

Any clues or suggestions.

What is the site?

See here: Error Message: Error 501/505: Not Implemented or Not Supported

Try running IE without Add-ons then try the site again.

Click Start then Run, type iexplore -extoff and press Enter or click on Go.
-- or --
Click on Start, Programs, Accessories, System Tools, Internet Explorer (No Add-ons)

Ztruker-
Thanks for your prompt reply.

The site in question is "http//www.katzeyeoptics.com"

Following the instructions in the microsoft support site I unchecked "use http 1.1" and "show friendly http message"

Still no joy. The "unfriendly" http message now reads: "GET to / not supported. Additionally a 404 Not Found error was encountered when trying ErrorDocment to handle request."

Next I followed your instructions to disable IE add-ons.
Still no joy.

I have contacted the owner of the URL and they claim that they have not had any problems at their end. There site seems to be functioning fine.

Additionally I have tried to ping the site and all packets sent are returned properly.

Thanks for your willingness to help. Any more ideas?

Just tried it on my work machine running XP(SP3)/IE8. No problems.

Have you tried the IP address directly? 67.222.136.72

Try it from Safe Mode with Networking, see if it works there. If so then something is running on your computer that is causing the problem.

Dwarf-
Thanks. I tried using the IP address you provided. It connects immediately to the home page of that site. However when I attempt to select a subpage on the site the same error occurs. Really weird.

Ztrucker-
Thanks. I am not sure I know how to try it from Safe Mode with Networking. I know how to boot computer in safe mode, but what are the next steps.

By the way I should have mentioned I am running Win 7/64. My service is provided by Verizon via DSL connection. And I repeat: I am able to connect with every other site I have tried, with no problem whatever.

Really appreciate your efforts.

This one works for me, didn't work with the first link though.

KatzEye™ Optics - Custom Focusing Screens

Blumesan, boot to the Windows Advanced Options menu (aka Safe Mode menu) and select Safe Mode with Networking. Then try your browser on the site you are having problems with, see what happens.

Ztruker

Thanks again. I booted in save mode with network option. No problem connecting to the site in question and no problem connecting to the linked pages on that site.

So now how do I determine what is causing the problem when I boot in normal mode?

Which means you have a program on your system that is preventing you from getting to that site. Most likely your A/V software or a third party firewall.