Hello Helga (and thank you Dominik!),
Thank you for the screen shot! It’s amazing how much one can tell from a single screen shot ;-)
The file your friend sent to you is encrypted with Version 2, but your friend has not used the key sharing feature and shared the access with you before sending it.
As Dominik says, your friend must add you to the list of key sharing recipients and then send the file again.
The key sharing function embeds the shared key into the file. The file must thus first be key shared with the recipient, then sent or file shared. Please note that AxCrypt does not share or send the actual file. To see a quick instructional video explaining how to use key sharing, please view https://www.youtube.com/watch?v=9z3KOZD-Yks .