It's pretty amazing how difficult this is...
My problem is, that BitLocker needs to be available for my product and the local group policy has to be available. It seems, that's not available on the home edition of Windows 10... so, but... when I use the GetProductInfo function (which may be deprectated? but who knows that exactely... it might be... anyway, let's assume it is not) ... then I have 96 (!!!!!!!!!!!!!) documented values I could get back and I have not seen about 60 of them until now and 12 do have the word "home" in them. So... which of those do not have the BitLocker and a working local group policy?
... well, you can say now "That's wrong what you do! You should try to find an interface and when it's available, then it's ok!" ... ok, fine... let's try this one. The nice thing here is, that I get an error when I try to find the Win32_EncryptableVolume wmi class on a 2012 R2 server (because the feature is not installed, but ... you know, it could be, so ... my product should still install here) but... Windows 10 Home says "yup... available" :-) ... and the interfaces for the gpo manipulation ... I guess they're also working in the home edition... didn't check that, but... how should this help in identifying the system?
... ok then. What's the idea now? ... working with those 96 values and simply hoping, that it works in most cases? ... great... really great... and I wasted hours because of this!