iPXE not passing PXE server name

Hi all,

I've been trying to deploy iPXE (ITMS 8.1 RU7) and have run into the following issue on my Windows Server 2008 R2 test site server: there is no servername in the URL to GetPxeScript.aspx (!!) (pic 1)

After running through the troubleshooting guide at https://support.symantec.com/en_US/article.TECH250831.html, Step 2.A.2.4, calling http://localhost:4433/iPXE/GetPxeScript.aspx) shows an error:
Could not load type 'Altiris.Deployment.Web.Services.GetPxeScript'.

I can see the site in IIS and the \bin directory does contain a Symantec.Deployment.Web.Services.dll, which I assume contains GetPxeScript.aspx.cs as referenced in the codebehind property of the ASP header tag.

If I add the missing servername, the URL resolves to a page of text with http references to various boot objects. For example:

http://${next-server}:4433/altiris/images/WinPE_iPXE/x64/pxeset.ini pxeset.ini initrd -n boot.wim

My guess is the unloaded ASP component is supposed to populate the ${next-server} value. I did check web.config,and the module reference is in place:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <location path="Altiris/Images">
        <system.webServer>
            <staticContent>
                <mimeMap fileExtension="." mimeType="application/octet-stream" />
                <mimeMap fileExtension=".*" mimeType="application/octet-stream" />
            </staticContent>
        </system.webServer>
    </location>
    <system.webServer>
        <modules>
            <add name="Altiris.Deployment.Web.Services.GetPxeScript" type="Symantec.Deployment.Web.Services" />
        </modules>
    </system.webServer>
</configuration>

That's where my diagnostics stopped. Happy to take any suggestions, advice, or solutions!

DMcG