Troubleshooting - Applies to Infiniti v8.0 or later. 

As Design launches a separate process (outside of Internet Explorer), it doesn't keep the credentials required to authenticate to your environment’s proxy server.

There are a couple of ways to overcome this:

Proxy 

Add a rule in the proxy to allow anonymous authentication to the website (e.g. http://intelledox.com)

Machine specific

Add an entry to the machine.config for the machines that will need to run Design. Detailed below:

Add the following to the machine.config file at:

C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\CONFIG

<configuration>
    <system.net>
        <defaultProxy enabled="true" useDefaultCredentials="true"/>
    </system.net>
</configuration>

The <configuration> tag is already present, so you just need to add the inner nodes.

For more information see this article: http://msdn.microsoft.com/en-us/library/kd3cf2ex.aspx

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