The GMTOOL need to use a different port since apache already is using port 80
Be suse you installed the IIS with CLASSIC ASPQuote:
When I hit this URL: http://localhost:5677/Admin/, I get this:
https://tinypic.host/i/screenshot-5.TTo10
I enter the user id and password that you mentioned to put in your 1st post admin as user id and password nd I get this error
https://tinypic.host/i/screenshot-3.TRzNq
https://i.imgur.com/v76T3VW.png
and enable Send Errors to Browser in IIS manager to see the error message
https://i.imgur.com/I9Qdi4a.png

