OnPremise region selection, show wrong decimal separator (comma instead of point)

wic

Hi,
I've a BC16.1 onPrem installation. Where can I change the regional settings to have a DOT instead of a COMMA in my decimal separator?
It looks like this is managed on the serverside (NST or IIS) - unfortunately, Microsoft decided to have a , for the swiss-French region- I changed it on the server but maybe only for my admin user, should I attack the registry?
Good to know:
- I changed it on my computer in the regional setting (excel is ok ..)
- If I connect to a BC "cloud", the "French-swiss" is correct

Thank for any idea
B.R.
Chris