I have an ISA Server 2006 Enterprise Edition NLB array and, intermittently, users connecting through one of the two servers get an ISA Server 403 (Forbidden) error message:
Technical Information (for support personnel)* Error Code: 403 Forbidden. The ISA Server denied the specified Uniform Resource Locator (URL). (12202)
* IP Address: [IP address of public web server
* Date: 6/17/2009 4:07:28 PM [GMT]
* Server: [DNS name of ISA server - always the same one]
* Source: proxy
The exact address that I get them on varies a lot.
I think that the problem is that it’s connecting to the other member of the array to access these sites and isn’t able to pass the authentication through (users are required to authenticate to access any website), but I have no idea where to even start to enable the authentication.
I had authentication set up wrongly – the authentication settings for web proxy on the intra-array network must be the same as the authentication settings on the internal network.
However, the servers shouldn’t have been connecting through one another to the internet in the first place.
That issue – the much more important one – was a problem with the binding order of the network adapters. Those nice Microsoft people have a fix.
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