Kind from you. I found in the meantime that Apple was so genious to create two different versions of a software. One that works exclusively from Mac to Mac and another one, with exactly the same name "Airdrop", that works exclusively from iphone to iphone. But you cannot communicate between Mac and iphone.
I found the software "Filedrop". It does what "Airdrop" is supposed to do. Install it as App from App-Store on your iPhone and install it from App-Store on your Mac. Page it in Google and download Filedrop on your PC. And from that moment you are finally free to transfer any kind of files between your machines.
Knows the devil why Appel is not willing to do things ike that?
Have a nice time - and thanks again!