Hi timbo343,
I have had many issues with this until I went for the easy route of using URL Rewrite (https://www.iis.net/downloads/microsoft/url-rewrite)
Set the following settings:
Match URL:
Requested URL: Matches the Pattern
Using: Regular Expressions
Pattern: (.*)
Ignore Case: Tick
Conditions
Local Grouping: Match All
ADD...
Condition Input: {HTTPS}
Check if input string: Matched the Pattern
Pattern: ^OFF$
Ignore Case: Tick
OK
Action
Action type: Redirect
Redirect URL: https://{HTTP_HOST}/{R:1}Append Query String: Tick
Redirect Type: See Other (303)
APPLY
Hope this help,
Thank you
