I am getting the IISADMIN was not found on server error warning when I click Apply in the Platform Installer Configuration UI..
It is Windows 11 with Internet Information Manager installed and all databases set up ok.
Username & Password are correct
Please see screenshots..
On prem doesn't support windows 11.
Created a Windows Serer 2019 VM and it installed ok.
Tried on a different machine and got the exact same issue :-(