.NET 6.0 MVC App returns 404 in IIS on Windows 10 - asp.net-mvc

Question

I've just refreshed an app written in .net 2.1 to .net 6.0. I worked through the errors and the site appears to compile cleanly. After I published to the server had many errors. Working through them, and standing up a full IIS install on my own machine, I now have it down to a 404 error.
When running the exe straight from the console it runs without errors.
Z:\ReportGroups>FleetLogix.ReportGroups.exe
warn: Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager[35]
No XML encryptor configured. Key {snip} may be persisted to storage in unencrypted form.
c:\inetpub\wwwroot\ReportGroups>FleetLogix.ReportGroups.exe
Hosting environment: Production
Content root path: c:\inetpub\wwwroot\ReportGroups
Now listening on: http://localhost:5000
Now listening on: https://localhost:5001
Application started. Press Ctrl+C to shut down.
Application is shutting down...
Web.config is
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<location path="." inheritInChildApplications="false">
<system.webServer>
<handlers>
<add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModuleV2" resourceType="Unspecified" />
</handlers>
<aspNetCore processPath="dotnet" arguments=".\FleetLogix.ReportGroups.dll" forwardWindowsAuthToken="false" startupTimeLimit="3600" requestTimeout="23:00:00" stdoutLogEnabled="false" hostingModel="inprocess" stdoutLogFile=".\logs\stdout" />
</system.webServer>
</location>
</configuration>
Looking through Event Viewer, there's nothing of note. System nothing for IIS, IIS-Configuration and IIS-Admin are empty.
Edit 2021-11-22
It took a morning, but I have Request Tracing installed. For those on windows 10, just go to Add Features > IIS > Health > Tracing. Don't believe the server 2012 pages. Below is a screenshot:
The actual xml and xslt were quite verbose.
I have reinstalled the Hosting package as administrator, just in case. The version installed was dotnet-hosting-6.0.0-win.exe. That didn't fix it. IIS was stopped/started at server level as well.
At the moment it looks like the handlerv2 is missing?
If any other logs or config are required please let me know

Answer 1

"At the moment it looks like the handlerv2 is missing?" is incorrect.
The correct interpretation of the FRT log is that ASP.NET Core module (handler configured in your web.config) runs fine, and decides that no routing rule yields a result for the incoming URL http://localhost/ReportGroups. Thus, it returns 404 as designed.
It is your responsibility to review IIS configuration (site/app) as well as your source code on routing to see what should be the right URL to use to access the target pages. And unless you share those parts, discussion on this question cannot move forward.