How do I find a Microsoft person to help a dev in Berlin work through code signing?

Here's a cry for help from a dev in Berlin (I'm in the UK):

'Simple thing: I want to pay Microsoft ten bucks a month to make it so that Windows users can download my app and it just open for them. Without that, Chrome won’t download it without an intervention, and after that intervention Windows will intervene. And will do so every time the app updates, which is about once a week.

But they will not take my money.'

Can anyone point me to a resource who can help?