We are running ISA Server 2006 Enterprise. All users use web proxy on port 8080 to browse the Internet from the Internal LAN. Our users can succesfully browse the Internet except when they want to access one specific web site. The web site is:
This is serious enough IMHO for M$ to release this in a patch all by itself. Why are they waiting for the next Service Pack to add this hotfix? Perhaps they're still testing it. Anyway, you can call the technical support number at http://support.microsoft.com/oas/default.aspx?ln=en-us&c1=10750&prid=10430&gprid=455046 and receive this hotfix free of charge. They will warn about using this in a production environment, so I would recommend caution... although I personally installed this hotfix w/o testing it. (We have a backup ISA server  that I can quickly switch over too, so I wasn't concerned).
Perhaps this is due to caching? I even disabled caching, restarted the server and re-enabled caching and still no luck. At any rate... my problems are solved as wellmark works :). Good luck. Please let me know how you fix it.
The hotfix worked for me! All the sites that you've listed did not work for me before the hotfix and now they work. The secret for me was the Reg entry that needs to be put in before the hotfix works!!!
Dear Guys, I want to replace my old ISA 2000 server with new ISA 2006. My ISA2006 joins an enterprise domain & all users will have to key-in their domain id in order to surf through proxy. But the problem is certain users when trying to surf, their is no authentication box appear instead of this error msg.
Error Code: 502 Proxy Error. The ISA Server denied the specified Uniform Resource Locator (URL). (12202)
I tried install hotfix that were given in Microsoft websites/engineer but the problem still happens. Need your guys expertise to help me solve this problem. Currently i've revert back to my old ISA 2000 server which has never encountered this kind of problem.
to access the internal web server. The IE7 browser gives me the error:
X Network Access Message: The page cannot be displayed
Explanation: There is a problem with the page you are trying to reach and it cannot be displayed.
.... .... Technical Information (for support personnel) Error Code: 502 Proxy Error. The HTTP message includes an unsupported header or an unsupported combination of headers. (12156) IP Address: 10.16.1.41 Date: 11/15/2007 12:47:31 AM [GMT] Server: cla-isa.scl.signet.com.au Source: proxy
Using FireFox V220.127.116.11 works fine and gives me the page I'm after.
However, if I replace the IP "10.16.1.41" with the host name "crs-cm", IE7 works fine! The same goes for IE6. And I have tested this on more than one workstation. This was not a problem when we were using ISA Server 2004.
This problem occurrs on our ISA Server CLA-ISA (10.3.0.48) V5.0.5721.240. Interestingly, the problem is not apparent when the user is using our second ISA Server CRS-ISA (10.16.1.100) V5.0.5721.240. The web server is local to the CRS-ISA server.
CLA-ISA & CRS-ISA Internal Network addressing:
10.0.0.0 to 10.255.255.255 172.16.0.0 to 172.31.255.255 192.168.0.0 to 192.168.255.255
Anyone know what's happening here??
| +-- JDMils | +-- Windows 2003 Server DC +-- Windows 2003 Server hosting ISA 2006 Stnd SP2 |
From: Lincoln, NE
Correction - If Firefox is set to use the ISA 2006 server, the site fails. The client succeeds if the Firefox browser uses the Fireall Client to access the site when there are not proxy settings configured.
In IE7, the client uses the web proxy even though the site is configured to bypass the proxy client on the ISA server.